drbd: track meta data IO intent, start and submit time

For diagnostic purposes, track intent, start time
and latest submit time of meta data IO.

Move separate members from struct drbd_device
into the embeded struct drbd_md_io.
s/md_io_(page|in_use)/md_io.\1/

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

1 files changed, 3 insertions, 6 deletions

diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c
index ad57129289b5..3978d9ec6f00 100644
--- a/drivers/block/drbd/drbd_worker.c
+++ b/drivers/block/drbd/drbd_worker.c
@@ -67,13 +67,10 @@ rwlock_t global_state_lock;
  */
 void drbd_md_io_complete(struct bio *bio, int error)
 {
-        struct drbd_md_io *md_io;
         struct drbd_device *device;
 
-        md_io = (struct drbd_md_io *)bio->bi_private;
-        device = container_of(md_io, struct drbd_device, md_io);
-
-        md_io->error = error;
+        device = bio->bi_private;
+        device->md_io.error = error;
 
         /* We grabbed an extra reference in _drbd_md_sync_page_io() to be able
          * to timeout on the lower level device, and eventually detach from it.
@@ -87,7 +84,7 @@ void drbd_md_io_complete(struct bio *bio, int error)
          * ASSERT(atomic_read(&device->md_io_in_use) == 1) there.
          */
         drbd_md_put_buffer(device);
-        md_io->done = 1;
+        device->md_io.done = 1;
         wake_up(&device->misc_wait);
         bio_put(bio);
         if (device->ldev) /* special case: drbd_md_read() during drbd_adm_attach() */