Anyone read this fantasy book?

I read a fantasy book some time ago and I can't remember what the title was but perhaps someone else does. The setting was on the inside of a planet or sphere if I remember correctly. The main characters were elves that had cities build on the leaves of massive trees. There were twinkling lights in the sky like stars that turned out to be ancient abandoned cities on the opposite side of the inside of their dome world. Dwarves lived in the roots of the massive trees. I remember they were attacked by blind telepathic giants who were the former servants of those who lived in the ancient cities and they would kill everything in their path.

I just have fuzzy general memories of the book since it was about 20 years ago that I read it. I believe it was part of a trilogy. If anyone has any idea what this book was I would appreciate it if you would share that information. Thanks!