在 2020/6/2 7:10, NeilBrown 写道:
On Mon, Jun 01 2020, yangerkun wrote:
We forget to call locks_move_blocks in posix_lock_inode when try to
process same owner and different types.
This patch is not necessary.
The caller of posix_lock_inode() must calls locks_delete_block() on
'request', and that will remove all blocked request and retry them.
So calling locks_move_blocks() here is at most an optimization. Maybe
it is a useful one.
What led you to suggesting this patch? Were you just examining the
code, or was there some problem that you were trying to solve?
Actually, case of this means just replace a exists file_lock. And once
we forget to call locks_move_blocks, the function call of
posix_lock_inode will also call locks_delete_block, and will wakeup all
blocked requests and retry them. But we should do this until we UNLOCK
the file_lock! So, it's really a bug here.
Thanks,
Kun.
Thanks,
NeilBrown
Signed-off-by: yangerkun <yangerkun@xxxxxxxxxx>
---
fs/locks.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/fs/locks.c b/fs/locks.c
index b8a31c1c4fff..36bd2c221786 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1282,6 +1282,7 @@ static int posix_lock_inode(struct inode *inode, struct file_lock *request,
if (!new_fl)
goto out;
locks_copy_lock(new_fl, request);
+ locks_move_blocks(new_fl, request);
request = new_fl;
new_fl = NULL;
locks_insert_lock_ctx(request, &fl->fl_list);
--
2.21.3
