Why are there little white bumps on the shaft of my penis?

Follicles/Glands: The bumps you are referring to are more than likely the hair follicles of the shaft. There may be prominent oil glands there as well. If these are small and pearl like and not red, on a stalk or causing a problem, it appears you have normal anatomy. One can get warts, orther virus induced lesions such as molluscum, herpes, syphillis and many other lesions on the penis. What you state is normal.