lightnvm: use end_io callback instead of instance

When the lightnvm core had the "gennvm" layer between the device and the
target, there was a need for the core to be able to figure out which
target it should send an end_io callback to. Leading to a "double"
end_io, first for the media manager instance, and then for the target
instance. Now that core and gennvm is merged, there is no longer a need
for this, and a single end_io callback will do.

Signed-off-by: Matias Bjørling <matias@cnexlabs.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c
index 80cd767..4f4db99 100644
--- a/drivers/lightnvm/core.c
+++ b/drivers/lightnvm/core.c
@@ -773,17 +773,16 @@
 }
 EXPORT_SYMBOL(nvm_free_rqd_ppalist);
 
-void nvm_end_io(struct nvm_rq *rqd, int error)
+void nvm_end_io(struct nvm_rq *rqd)
 {
 	struct nvm_tgt_dev *tgt_dev = rqd->dev;
-	struct nvm_tgt_instance *ins = rqd->ins;
 
 	/* Convert address space */
 	if (tgt_dev)
 		nvm_rq_dev_to_tgt(tgt_dev, rqd);
 
-	rqd->error = error;
-	ins->tt->end_io(rqd);
+	if (rqd->end_io)
+		rqd->end_io(rqd);
 }
 EXPORT_SYMBOL(nvm_end_io);
 
diff --git a/drivers/lightnvm/rrpc.c b/drivers/lightnvm/rrpc.c
index 9fb7de3..e00b1d7 100644
--- a/drivers/lightnvm/rrpc.c
+++ b/drivers/lightnvm/rrpc.c
@@ -779,7 +779,7 @@
 
 static void rrpc_end_io(struct nvm_rq *rqd)
 {
-	struct rrpc *rrpc = container_of(rqd->ins, struct rrpc, instance);
+	struct rrpc *rrpc = rqd->private;
 	struct nvm_tgt_dev *dev = rrpc->dev;
 	struct rrpc_rq *rrqd = nvm_rq_to_pdu(rqd);
 	uint8_t npages = rqd->nr_ppas;
@@ -972,8 +972,9 @@
 
 	bio_get(bio);
 	rqd->bio = bio;
-	rqd->ins = &rrpc->instance;
+	rqd->private = rrpc;
 	rqd->nr_ppas = nr_pages;
+	rqd->end_io = rrpc_end_io;
 	rrq->flags = flags;
 
 	err = nvm_submit_io(dev, rqd);
@@ -1532,7 +1533,6 @@
 	if (!rrpc)
 		return ERR_PTR(-ENOMEM);
 
-	rrpc->instance.tt = &tt_rrpc;
 	rrpc->dev = dev;
 	rrpc->disk = tdisk;
 
@@ -1611,7 +1611,6 @@
 
 	.make_rq	= rrpc_make_rq,
 	.capacity	= rrpc_capacity,
-	.end_io		= rrpc_end_io,
 
 	.init		= rrpc_init,
 	.exit		= rrpc_exit,
diff --git a/drivers/lightnvm/rrpc.h b/drivers/lightnvm/rrpc.h
index 94e4d73..fdb6ff9 100644
--- a/drivers/lightnvm/rrpc.h
+++ b/drivers/lightnvm/rrpc.h
@@ -102,9 +102,6 @@
 };
 
 struct rrpc {
-	/* instance must be kept in top to resolve rrpc in unprep */
-	struct nvm_tgt_instance instance;
-
 	struct nvm_tgt_dev *dev;
 	struct gendisk *disk;