Does ata_exec_internal_sg sleep?
 

I'm comparing the sata portion of various Operating Systems. There's something I can not sure about ata_exec_internal_sg. When this function is going to use an ata port, it accquires a spin lock. This seems very different from FreeBSD and OpenSolaris since the two both spin first and then sleep. I did not find spin_lock_irqsave involvle any sleep possibility. Moreover, the comment says that this function "might sleep", does it exclusively mean wait_for_completion_timeout?