Jofu is a person in the Edo period who lived permanently in Edo and served seii taishogun (literally, "great general who subdued the barbarians") without performing Sankinkotai (a system under which feudal lords in the Edo period were required to spend every other year in residence in Edo).
Hatamoto (direct retainers of the bakufu, which is a form of Japanese feudal government headed by a shogun) and gokenin (immediate vassals of the shogunate) except kotaiyoriai (alternate yoriai, a family status of samurai warriors) who performed Sankinkotai were Jofu because they lived permanently in Edo and served seii taishogun.
As for all kinds of Daimyo (Japanese feudal lord), Mito Tokugawa family (Mito Domain) who were obligated to live permanently in Edo by Ieyasu TOKUGAWA and lords of domains (mainly fudai daimyo [a daimyo in hereditary vassal to the Tokugawa family]) who held public posts of Edo bakufu including roju (member of shogun's council of elders), wakadoshiyori (a managerial position in Edo bakufu), and jisha-bugyo (magistrate of temples and shrines) and stationed at Edo-jo Castle were of course Jofu because they needed to live permanently in Edo.
And, as for feudal retainers of domains (baishin [indirect vassal] of shogun), someone who worked at edohantei (residence maintained by a daimyo in Edo) on a full-time basis (or someone whose family member worked in Edo on a full-time basis) was called jofu. Many of jofu feudal retainers of domains had families and bodai-ji or danna-dera (family temples) in Edo, and if they died in Edo, their bodies and cremains were not brought back to their hometowns.
On the other hand, someone who returned to his hometown when the lord of domain performed Sankinkotai was called Edo-zume (working in Edo) and distinguished from jofu.