block: kill swap_io_context()

It blindly copies everything in the io_context, including the lock.
That doesn't work so well for either lock ordering or lockdep.

There seems zero point in swapping io contexts on a request to request
merge, so the best point of action is to just remove it.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 0 insertions, 1 deletions

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index cf170391..90392a9 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -39,7 +39,6 @@ void exit_io_context(void);
 struct io_context *get_io_context(gfp_t gfp_flags, int node);
 struct io_context *alloc_io_context(gfp_t gfp_flags, int node);
 void copy_io_context(struct io_context **pdst, struct io_context **psrc);
-void swap_io_context(struct io_context **ioc1, struct io_context **ioc2);
 
 struct request;
 typedef void (rq_end_io_fn)(struct request *, int);