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 <[e-mail]>
Signed-off-by: Jens Axboe <[e-mail]>

drivers/block/null_blk.c

···
 {
 	struct nvm_rq *rqd = rq->end_io_data;
 
-	nvm_end_io(rqd, error);
+	rqd->error = error;
+	nvm_end_io(rqd);
 
 	blk_put_request(rq);
 }

drivers/lightnvm/core.c

···
 }
 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);
 

drivers/lightnvm/rrpc.c

···
 
 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;
···
 
 	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);
···
 	if (!rrpc)
 		return ERR_PTR(-ENOMEM);
 
-	rrpc->instance.tt = &tt_rrpc;
 	rrpc->dev = dev;
 	rrpc->disk = tdisk;
 
···
 
 	.make_rq	= rrpc_make_rq,
 	.capacity	= rrpc_capacity,
-	.end_io		= rrpc_end_io,
 
 	.init		= rrpc_init,
 	.exit		= rrpc_exit,

drivers/lightnvm/rrpc.h

···
 };
 
 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;
 

drivers/nvme/host/lightnvm.c

···
 	struct nvm_rq *rqd = rq->end_io_data;
 
 	rqd->ppa_status = nvme_req(rq)->result.u64;
-	nvm_end_io(rqd, error);
+	rqd->error = error;
+	nvm_end_io(rqd);
 
 	kfree(nvme_req(rq)->cmd);
 	blk_mq_free_request(rq);

include/linux/lightnvm.h

···
 	struct gendisk *disk;
 };
 
-struct nvm_tgt_instance {
-	struct nvm_tgt_type *tt;
-};
-
 #define ADDR_EMPTY (~0ULL)
 
 #define NVM_VERSION_MAJOR 1
···
 typedef void (nvm_end_io_fn)(struct nvm_rq *);
 
 struct nvm_rq {
-	struct nvm_tgt_instance *ins;
 	struct nvm_tgt_dev *dev;
 
 	struct bio *bio;
···
 
 	u64 ppa_status; /* ppa media status */
 	int error;
+
+	void *private;
 };
 
 static inline struct nvm_rq *nvm_rq_from_pdu(void *pdu)
···
 	/* target entry points */
 	nvm_tgt_make_rq_fn *make_rq;
 	nvm_tgt_capacity_fn *capacity;
-	nvm_end_io_fn *end_io;
 
 	/* module-specific init/teardown */
 	nvm_tgt_init_fn *init;
···
 			   void *);
 extern int nvm_get_area(struct nvm_tgt_dev *, sector_t *, sector_t);
 extern void nvm_put_area(struct nvm_tgt_dev *, sector_t);
-extern void nvm_end_io(struct nvm_rq *, int);
+extern void nvm_end_io(struct nvm_rq *);
 extern int nvm_bb_tbl_fold(struct nvm_dev *, u8 *, int);
 extern int nvm_get_tgt_bb_tbl(struct nvm_tgt_dev *, struct ppa_addr, u8 *);