Fire up the barbecue and put the rack about 10cm from the coals.
Chop tomatoes and combine with onion, chilli, coriander, lime juice and salt to taste. Set aside.
Rub the salmon with a little oil and sprinkle with salt and pepper. Put it on the barbecue grill skin side down and let sit 4-5 minutes then turn and cook 3 minutes more - don't overcook.