diff options
Diffstat (limited to 'drivers/block')
| -rw-r--r-- | drivers/block/drbd/drbd_worker.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c index 933091ffefca..62bde5ae17f7 100644 --- a/drivers/block/drbd/drbd_worker.c +++ b/drivers/block/drbd/drbd_worker.c @@ -77,10 +77,21 @@ void drbd_md_io_complete(struct bio *bio, int error) 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. + * If this io completion runs after that timeout expired, this + * drbd_md_put_buffer() may allow us to finally try and re-attach. + * During normal operation, this only puts that extra reference + * down to 1 again. + * Make sure we first drop the reference, and only then signal + * completion, or we may (in drbd_al_read_log()) cycle so fast into the + * next drbd_md_sync_page_io(), that we trigger the + * ASSERT(atomic_read(&mdev->md_io_in_use) == 1) there. + */ + drbd_md_put_buffer(mdev); md_io->done = 1; wake_up(&mdev->misc_wait); bio_put(bio); - drbd_md_put_buffer(mdev); put_ldev(mdev); } |