lightnvm: introduce max_phys_sects helper function

Target devices do not have access to the device driver operations.
Introduce a helper function that exposes the max. number of physical
sectors supported by the underlying device.

Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>

drivers/lightnvm/core.c

@@ -203,6 +203,14 @@ int nvm_set_bb_tbl(struct nvm_dev *dev, struct ppa_addr *ppas, int nr_ppas,
 }
 EXPORT_SYMBOL(nvm_set_bb_tbl);
 
+int nvm_max_phys_sects(struct nvm_tgt_dev *tgt_dev)
+{
+	struct nvm_dev *dev = tgt_dev->parent;
+
+	return dev->ops->max_phys_sect;
+}
+EXPORT_SYMBOL(nvm_max_phys_sects);
+
 int nvm_submit_io(struct nvm_tgt_dev *tgt_dev, struct nvm_rq *rqd)
 {
 	struct nvm_dev *dev = tgt_dev->parent;

include/linux/lightnvm.h

@@ -529,6 +529,7 @@ extern void nvm_unregister(struct nvm_dev *);
 extern int nvm_set_bb_tbl(struct nvm_dev *dev, struct ppa_addr *ppas,
 							int nr_ppas, int type);
 
+extern int nvm_max_phys_sects(struct nvm_tgt_dev *);
 extern int nvm_submit_io(struct nvm_tgt_dev *, struct nvm_rq *);
 extern void nvm_generic_to_addr_mode(struct nvm_dev *, struct nvm_rq *);
 extern void nvm_addr_to_generic_mode(struct nvm_dev *, struct nvm_rq *);