The quality loss is not that big, although if you need the highest quality possible, then dividing the bitmap or making large textures is the only option. I once needed a 1024x768 background image and I simply used multiple 256x256 textures to do it. For instance, you're having 800x600 image you want to render, extend it to 1024x768 and then use textures with size of 256x256 and pattern size of 256x256. That way you got 3x2 patterns and you simply draw them on the screen.

Hope this helps,
Lifepower