drbd: reduce code duplication when receiving data requests
also canonicalize the return values of read_for_csum
and drbd_rs_begin_io to return -ESOMETHING, or 0 for success.
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_worker.c b/drivers/block/drbd/drbd_worker.c
index 53b7425..f5d779b 100644
--- a/drivers/block/drbd/drbd_worker.c
+++ b/drivers/block/drbd/drbd_worker.c
@@ -374,26 +374,26 @@
struct drbd_epoch_entry *e;
if (!get_ldev(mdev))
- return 0;
+ return -EIO;
/* GFP_TRY, because if there is no memory available right now, this may
* be rescheduled for later. It is "only" background resync, after all. */
e = drbd_alloc_ee(mdev, DRBD_MAGIC+0xbeef, sector, size, GFP_TRY);
if (!e)
- goto fail;
+ goto defer;
+ e->w.cb = w_e_send_csum;
spin_lock_irq(&mdev->req_lock);
list_add(&e->w.list, &mdev->read_ee);
spin_unlock_irq(&mdev->req_lock);
- e->w.cb = w_e_send_csum;
if (drbd_submit_ee(mdev, e, READ, DRBD_FAULT_RS_RD) == 0)
- return 1;
+ return 0;
drbd_free_ee(mdev, e);
-fail:
+defer:
put_ldev(mdev);
- return 2;
+ return -EAGAIN;
}
void resync_timer_fn(unsigned long data)
@@ -649,15 +649,19 @@
size = (capacity-sector)<<9;
if (mdev->agreed_pro_version >= 89 && mdev->csums_tfm) {
switch (read_for_csum(mdev, sector, size)) {
- case 0: /* Disk failure*/
+ case -EIO: /* Disk failure */
put_ldev(mdev);
return 0;
- case 2: /* Allocation failed */
+ case -EAGAIN: /* allocation failed, or ldev busy */
drbd_rs_complete_io(mdev, sector);
mdev->bm_resync_fo = BM_SECT_TO_BIT(sector);
i = rollback_i;
goto requeue;
- /* case 1: everything ok */
+ case 0:
+ /* everything ok */
+ break;
+ default:
+ BUG();
}
} else {
inc_rs_pending(mdev);