NAME

tran_dmafree - SCSI HBA DMA deallocation entry point

SYNOPSIS

#include <sys/scsi/scsi.h>

void prefixtran_dmafree(struct scsi_address * ap, struct scsi_pkt * pkt);

INTERFACE LEVEL

Solaris architecture specific (Solaris DDI).

ARGUMENTS

ap

A pointer to a scsi_address(9S) structure.

pkt

A pointer to a scsi_pkt(9S) structure.

DESCRIPTION

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

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.

SEE ALSO

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

NOTES

A target driver may call tran_dmafree( ) on packets for which no DMA resources were allocated.