Are Uways al-Qarani, Hasan al-Basri, Imam al-Ghazali, and Shaykh Abd al-Qadir al-Jilani considered imams of Sufism? And if so, did they call people to enter Sufism as part of Islam, or is the Sufis' citing of them due to other reasons?

Sufism is a newly coined term that was not known in the first three centuries of Islam. The term "Sufism" appeared in Kufa, and scholars and historians disputed who was the first to be called by it. Some said it was Abu Hashim al-Kufi, some said it was 'Abdak, and some said it was Jabir ibn Hayyan. Attributing Uwais al-Qarni and Hasan al-Basri to Sufism in the technical sense is false, because Sufism had not yet emerged in their time. Their frequent mention in Sufi books is because they were prominent figures in asceticism and ethics, and because the authors of those books wanted to benefit from the Ummah's acceptance of them to prove the legitimacy of Sufism. The inclusion of their sayings in Sufi books does not mean that they were Sufis; rather, the matter refers to what was authentically established from them and from other Salaf through sound chains of narration.