lightnvm: pblk: add initialization check

Add a sanity check to the pblk initialization sequence in order to
ensure that enough LUNs have been allocated to store the line metadata.

Signed-off-by: Javier González <[e-mail]>
Signed-off-by: Matias Bjørling <[e-mail]>
Signed-off-by: Jens Axboe <[e-mail]>

drivers/lightnvm/pblk-init.c

···
 	lm->emeta_bb = geo->nr_luns - i;
 	lm->min_blk_line = 1 + DIV_ROUND_UP(lm->smeta_sec + lm->emeta_sec[0],
 							geo->sec_per_blk);
+	if (lm->min_blk_line > lm->blk_per_line) {
+		pr_err("pblk: config. not supported. Min. LUN in line:%d\n",
+							lm->blk_per_line);
+		ret = -EINVAL;
+		goto fail;
+	}
 
 	ret = pblk_lines_alloc_metadata(pblk);
 	if (ret)