TRAN_DMAFREE(9E) Driver Entry Points TRAN_DMAFREE(9E)

tran_dmafree - SCSI HBA DMA deallocation entry point 

#include <sys/scsi/scsi.h>
 void prefixtran_dmafree(struct scsi_address *ap, struct scsi_pkt *pkt);

illumos architecture specific (illumos DDI).

ap
A pointer to a scsi_address structure. See scsi_address(9S).

pkt

A pointer to a scsi_pkt structure. See scsi_pkt(9S).

The tran_dmafree() vector in the scsi_hba_tran structure must be initialized during the HBA driver's attach() to point to an HBA entry point to be called when a target driver calls scsi_dmafree(9F). See attach(9E) and scsi_hba_tran(9S).

tran_dmafree() must deallocate any DMA resources previously allocated to this pkt in a call to tran_init_pkt(9E). tran_dmafree() should not free the structure pointed to by pkt itself. Since tran_destroy_pkt(9E) must also free DMA resources, it is important that the HBA driver keeps accurate note of whether scsi_pkt(9S) structures have DMA resources allocated.

attach(9E), tran_destroy_pkt(9E), tran_init_pkt(9E), scsi_dmafree(9F), scsi_dmaget(9F), scsi_hba_attach(9F), scsi_init_pkt(9F), scsi_address(9S), scsi_hba_tran(9S), scsi_pkt(9S)

Writing Device Drivers

A target driver may call tran_dmafree() on packets for which no DMA resources were allocated.
August 30, 1995 OmniOS