1. NAME▲
atapi_check_dma - Check whether ATAPI DMA can be supported
2. SYNOPSIS ▲
int atapi_check_dma(struct ata_queued_cmd * qc );
3. ARGUMENTS ▲
qc 
    Metadata associated with taskfile to check 
4. DESCRIPTION ▲
Allow low-level driver to filter ATA PACKET commands, returning a status indicating whether or not it is OK to use DMA for the supplied PACKET command.
5. LOCKING ▲
spin_lock_irqsave(host lock)
6. RETURNS ▲
0 when ATAPI DMA can be used nonzero otherwise
7. AUTHOR ▲
Jeff Garzik 
    Author. 
8. COPYRIGHT ▲