block: remove BLKDEV_IFL_WAIT

All the blkdev_issue_* helpers can only sanely be used for synchronous
caller.  To issue cache flushes or barriers asynchronously the caller needs
to set up a bio by itself with a completion callback to move the asynchronous
state machine ahead.  So drop the BLKDEV_IFL_WAIT flag that is always
specified when calling blkdev_issue_* and also remove the now unused flags
argument to blkdev_issue_flush and blkdev_issue_zeroout.  For
blkdev_issue_discard we need to keep it for the secure discard flag, which
gains a more descriptive name and loses the bitops vs flag confusion.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2 files changed, 2 insertions, 3 deletions

diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index 352441b0f92f..c2ef476f5711 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -2321,8 +2321,7 @@ static inline void drbd_md_flush(struct drbd_conf *mdev)
         if (test_bit(MD_NO_BARRIER, &mdev->flags))
                 return;
 
-        r = blkdev_issue_flush(mdev->ldev->md_bdev, GFP_KERNEL, NULL,
-                        BLKDEV_IFL_WAIT);
+        r = blkdev_issue_flush(mdev->ldev->md_bdev, GFP_KERNEL, NULL);
         if (r) {
                 set_bit(MD_NO_BARRIER, &mdev->flags);
                 dev_err(DEV, "meta data flush failed with status %d, disabling md-flushes\n", r);
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index 081522d3c742..df15e7f0e7b7 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -975,7 +975,7 @@ static enum finish_epoch drbd_flush_after_epoch(struct drbd_conf *mdev, struct d
 
         if (mdev->write_ordering >= WO_bdev_flush && get_ldev(mdev)) {
                 rv = blkdev_issue_flush(mdev->ldev->backing_bdev, GFP_KERNEL,
-                                        NULL, BLKDEV_IFL_WAIT);
+                                        NULL);
                 if (rv) {
                         dev_err(DEV, "local disk flush failed with status %d\n", rv);
                         /* would rather check on EOPNOTSUPP, but that is not reliable.