'\" te
.\"  Copyright (c) 1997, Sun Microsystems, Inc.  All Rights Reserved
.TH tran_dmafree 9E "30 Aug 1995" "SunOS 5.11" "Driver Entry Points"
.SH NAME
tran_dmafree \- SCSI HBA DMA deallocation entry point
.SH SYNOPSIS
.LP
.nf
#include <sys/scsi/scsi.h>

\fB void prefix\fR\fBtran_dmafree\fR(\fBstruct scsi_address *\fR\fIap\fR, \fBstruct scsi_pkt *\fR\fIpkt\fR);
.fi

.SH INTERFACE LEVEL
.sp
.LP
Solaris architecture specific (Solaris DDI).
.SH ARGUMENTS
.sp
.ne 2
.mk
.na
\fB\fIap\fR\fR
.ad
.RS 8n
.rt  
A pointer to a \fIscsi_address\fR structure. See \fBscsi_address\fR(9S). 
.RE

.sp
.ne 2
.mk
.na
\fB\fIpkt\fR \fR
.ad
.RS 8n
.rt  
A pointer to a \fIscsi_pkt\fR  structure. See \fBscsi_pkt\fR(9S).
.RE

.SH DESCRIPTION
.sp
.LP
The \fBtran_dmafree()\fR vector in the \fIscsi_hba_tran\fR structure must be initialized during the \fBHBA \fRdriver's \fBattach()\fR to point to an \fBHBA \fRentry point to be called when a target driver calls \fBscsi_dmafree\fR(9F). See \fBattach\fR(9E) and \fBscsi_hba_tran\fR(9S).
.sp
.LP
\fBtran_dmafree()\fR must deallocate any \fBDMA \fRresources previously allocated to this  \fIpkt\fR in a call to \fBtran_init_pkt\fR(9E). \fBtran_dmafree()\fR should not free the structure pointed to by \fIpkt\fR itself. Since  \fBtran_destroy_pkt\fR(9E) must also free \fBDMA \fRresources, it is important that the \fBHBA \fRdriver keeps accurate note of whether \fBscsi_pkt\fR(9S) structures have \fBDMA \fRresources allocated.
.SH SEE ALSO
.sp
.LP
\fBattach\fR(9E), \fBtran_destroy_pkt\fR(9E), \fBtran_init_pkt\fR(9E), \fBscsi_dmafree\fR(9F), \fBscsi_dmaget\fR(9F), \fBscsi_hba_attach\fR(9F), \fBscsi_init_pkt\fR(9F), \fBscsi_address\fR(9S), \fBscsi_hba_tran\fR(9S), \fBscsi_pkt\fR(9S) 
.sp
.LP
\fIWriting Device Drivers for Oracle Solaris 11.2\fR 
.SH NOTES
.sp
.LP
A target driver may call \fBtran_dmafree()\fR on packets for which no \fBDMA \fRresources were allocated.