drbd: drbd_md_sync_page_io(): Return 0 upon success and an error code otherwise

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
diff --git a/drivers/block/drbd/drbd_actlog.c b/drivers/block/drbd/drbd_actlog.c
index 6517c91..5867761 100644
--- a/drivers/block/drbd/drbd_actlog.c
+++ b/drivers/block/drbd/drbd_actlog.c
@@ -151,7 +151,7 @@
 int drbd_md_sync_page_io(struct drbd_conf *mdev, struct drbd_backing_dev *bdev,
 			 sector_t sector, int rw)
 {
-	int ok;
+	int err;
 	struct page *iop = mdev->md_io_page;
 
 	D_ASSERT(mutex_is_locked(&mdev->md_io_mutex));
@@ -168,14 +168,12 @@
 		     current->comm, current->pid, __func__,
 		     (unsigned long long)sector, (rw & WRITE) ? "WRITE" : "READ");
 
-	ok = !_drbd_md_sync_page_io(mdev, bdev, iop, sector, rw, MD_BLOCK_SIZE);
-	if (unlikely(!ok)) {
+	err = _drbd_md_sync_page_io(mdev, bdev, iop, sector, rw, MD_BLOCK_SIZE);
+	if (err) {
 		dev_err(DEV, "drbd_md_sync_page_io(,%llus,%s) failed!\n",
 		    (unsigned long long)sector, (rw & WRITE) ? "WRITE" : "READ");
-		return 0;
 	}
-
-	return ok;
+	return err;
 }
 
 static struct lc_element *_al_get(struct drbd_conf *mdev, unsigned int enr)
@@ -392,7 +390,7 @@
 	if (drbd_bm_write_hinted(mdev))
 		aw->err = -EIO;
 		/* drbd_chk_io_error done already */
-	else if (!drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) {
+	else if (drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) {
 		aw->err = -EIO;
 		drbd_chk_io_error(mdev, 1, true);
 	} else {
@@ -439,7 +437,7 @@
 
 	/* Dont process error normally,
 	 * as this is done before disk is attached! */
-	if (!drbd_md_sync_page_io(mdev, bdev, sector, READ))
+	if (drbd_md_sync_page_io(mdev, bdev, sector, READ))
 		return -1;
 
 	if (!expect(b->magic == cpu_to_be32(DRBD_AL_MAGIC)))
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 6c4454c..43b9b7a 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -2637,7 +2637,7 @@
 	D_ASSERT(drbd_md_ss__(mdev, mdev->ldev) == mdev->ldev->md.md_offset);
 	sector = mdev->ldev->md.md_offset;
 
-	if (!drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) {
+	if (drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) {
 		/* this was a try anyways ... */
 		dev_err(DEV, "meta data update failed!\n");
 		drbd_chk_io_error(mdev, 1, true);
@@ -2670,7 +2670,7 @@
 	mutex_lock(&mdev->md_io_mutex);
 	buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
 
-	if (!drbd_md_sync_page_io(mdev, bdev, bdev->md.md_offset, READ)) {
+	if (drbd_md_sync_page_io(mdev, bdev, bdev->md.md_offset, READ)) {
 		/* NOTE: can't do normal error processing here as this is
 		   called BEFORE disk is attached */
 		dev_err(DEV, "Error while reading metadata.\n");