A compressor includes a rotary shaft, a cam, a cylinder block, pistons, a thrust bearing, a rotary valve, and an oil passage. The rotary shaft has an in-shaft passage formed therein. The cam rotates integrally with the rotary shaft. The pistons are coupled to the rotary shaft through the cam. The thrust bearing is provided between the cam and the cylinder block. The thrust bearing includes a first race in contact with the cam, a second race in contact with the cylinder block, and rolling elements retained between the first and second races to form a gap therebetween. The oil passage extends from the gap to the in-shaft passage and includes an oil retaining space formed in at least one of the cam and the cylinder block.