lightnvm: move device L2P detection to core

A 1.2 device is able to manage the logical to physical mapping
table internally or leave it to the host.

A target only supports one of those approaches, and therefore must
check on initialization. Move this check to core to avoid each target
implement the check.
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/lightnvm/core.c

@@ -355,6 +355,11 @@ static int nvm_create_tgt(struct nvm_dev *dev, struct nvm_ioctl_create *create)
 		return -EINVAL;
 	}
 
+	if ((tt->flags & NVM_TGT_F_HOST_L2P) != (dev->geo.dom & NVM_RSP_L2P)) {
+		pr_err("nvm: device is incompatible with target L2P type.\n");
+		return -EINVAL;
+	}
+
 	if (nvm_target_exists(create->tgtname)) {
 		pr_err("nvm: target name already exists (%s)\n",
 							create->tgtname);

drivers/lightnvm/pblk-init.c

@@ -1210,13 +1210,6 @@ static void *pblk_init(struct nvm_tgt_dev *dev, struct gendisk *tdisk,
 		return ERR_PTR(-EINVAL);
 	}
 
-	if (geo->version == NVM_OCSSD_SPEC_12 && geo->dom & NVM_RSP_L2P) {
-		pblk_err(pblk, "host-side L2P table not supported. (%x)\n",
-							geo->dom);
-		kfree(pblk);
-		return ERR_PTR(-EINVAL);
-	}
-
 	spin_lock_init(&pblk->resubmit_lock);
 	spin_lock_init(&pblk->trans_lock);
 	spin_lock_init(&pblk->lock);

include/linux/lightnvm.h

@@ -495,9 +495,15 @@ typedef void (nvm_tgt_exit_fn)(void *, bool);
 typedef int (nvm_tgt_sysfs_init_fn)(struct gendisk *);
 typedef void (nvm_tgt_sysfs_exit_fn)(struct gendisk *);
 
+enum {
+	NVM_TGT_F_DEV_L2P = 0,
+	NVM_TGT_F_HOST_L2P = 1 << 0,
+};
+
 struct nvm_tgt_type {
 	const char *name;
 	unsigned int version[3];
+	int flags;
 
 	/* target entry points */
 	nvm_tgt_make_rq_fn *make_rq;