'\" te
.\" Copyright (c) 2006, Sun Microsystems, Inc., All Rights Reserved
.\" The contents of this file are subject to the terms of the Common Development and Distribution License (the "License").  You may not use this file except in compliance with the License.
.\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing.  See the License for the specific language governing permissions and limitations under the License.
.\" When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE.  If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
.TH get_pktiopb 9F "16 Jan 2006" "SunOS 5.11" "Kernel Functions for Drivers"
.SH NAME
get_pktiopb, free_pktiopb \- allocate/free a SCSI packet in the iopb map
.SH SYNOPSIS
.LP
.nf
#include <sys/scsi/scsi.h> 



\fBstruct scsi_pkt *\fR\fBget_pktiopb\fR(\fBstruct scsi_address *\fR\fIap\fR,
     \fBcaddr_t *\fR\fIdatap\fR, \fBint\fR \fIcdblen\fR, \fBint\fR \fIstatuslen\fR, \fBint\fR \fIdatalen\fR, 
     \fBint\fR \fIreadflag\fR, \fBint (*\fR\fIcallback\fR);
.fi

.LP
.nf
\fBvoid\fR \fBfree_pktiopb\fR(\fBstruct scsi_pkt *\fR\fIpkt\fR, \fBcaddr_t\fR \fIdatap\fR, \fBint\fR \fIdatalen\fR);
.fi

.SH INTERFACE LEVEL
.sp
.LP
These interfaces are obsolete. Use \fBscsi_alloc_consistent_buf\fR(9F) instead
of \fBget_pktiopb()\fR. Use \fBscsi_free_consistent_buf\fR(9F) instead of
\fBfree_pktiopb()\fR.
.SH PARAMETERS
.sp
.ne 2
.mk
.na
\fB\fIap\fR\fR
.ad
.RS 13n
.rt  
Pointer to the target's \fBscsi_address\fR structure.
.RE

.sp
.ne 2
.mk
.na
\fB\fIdatap\fR\fR
.ad
.RS 13n
.rt  
Pointer to the address of the packet, set by this function.
.RE

.sp
.ne 2
.mk
.na
\fB\fIcdblen\fR\fR
.ad
.RS 13n
.rt  
Number of bytes required for the \fBSCSI \fRcommand descriptor block (CDB).
.RE

.sp
.ne 2
.mk
.na
\fB\fIstatuslen\fR\fR
.ad
.RS 13n
.rt  
Number of bytes required for the \fBSCSI \fRstatus area.
.RE

.sp
.ne 2
.mk
.na
\fB\fIdatalen\fR\fR
.ad
.RS 13n
.rt  
Number of bytes required for the data area of the \fBSCSI \fRcommand.
.RE

.sp
.ne 2
.mk
.na
\fB\fIreadflag\fR\fR
.ad
.RS 13n
.rt  
If non-zero, data will be transferred from the \fBSCSI \fRtarget.
.RE

.sp
.ne 2
.mk
.na
\fB\fIcallback\fR\fR
.ad
.RS 13n
.rt  
Pointer to a callback function, or \fBNULL_FUNC\fR or \fBSLEEP_FUNC\fR
.RE

.sp
.ne 2
.mk
.na
\fB\fIpkt\fR\fR
.ad
.RS 13n
.rt  
Pointer to a \fBscsi_pkt\fR(9S) structure.
.RE

.SH DESCRIPTION
.sp
.LP
The \fBget_pktiopb()\fR function allocates a \fBscsi_pkt\fR structure that has
a small data area allocated. It is used by some \fBSCSI \fRcommands such as
\fBREQUEST_SENSE\fR, which involve a small amount of data and require
cache-consistent memory for proper operation. It uses \fBddi_iopb_alloc\fR(9F)
for allocating the data area and \fBscsi_resalloc\fR(9F) to allocate the packet
and \fBDMA\fR resources.
.sp
.LP
\fIcallback\fR indicates what \fBget_pktiopb()\fR should do when resources are
not available:
.sp
.ne 2
.mk
.na
\fB\fBNULL_FUNC\fR\fR
.ad
.RS 16n
.rt  
Do not wait for resources. Return a \fINULL\fR pointer.
.RE

.sp
.ne 2
.mk
.na
\fB\fBSLEEP_FUNC\fR\fR
.ad
.RS 16n
.rt  
Wait indefinitely for resources.
.RE

.sp
.ne 2
.mk
.na
\fBOther Values\fR
.ad
.RS 16n
.rt  
\fIcallback\fR points to a function which is called when resources may have
become available. \fIcallback\fR \fBmust\fR return either \fB0\fR (indicating
that it attempted to allocate resources but failed to do so again), in which
case it is put back on a list to be called again later, or \fB1\fR indicating
either success in allocating resources or indicating that it no longer cares
for a retry.
.RE

.sp
.LP
The \fBfree_pktiopb()\fR function is used for freeing the packet and its
associated resources.
.SH RETURN VALUES
.sp
.LP
The \fBget_pktiopb()\fR function returns a pointer to the newly allocated
\fBscsi_pkt\fR or a \fINULL\fR pointer.
.SH CONTEXT
.sp
.LP
If \fIcallback\fR is \fBSLEEP_FUNC\fR, then this routine can be called only
from user or kernel context. Otherwise, it can be called from user, interrupt,
or kernel context. The \fIcallback\fR function should not block or call
routines that block.
.sp
.LP
The \fBfree_pktiopb()\fR function can be called from user, interrupt, or kernel
context.
.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(5) for a description of the following attributes:
.sp

.sp
.TS
tab() box;
cw(2.75i) |cw(2.75i) 
lw(2.75i) |lw(2.75i) 
.
\fBATTRIBUTE TYPE\fR\fBATTRIBUTE VALUE\fR
_
Stability LevelObsolete
.TE

.SH SEE ALSO
.sp
.LP
\fBattributes\fR(5), \fBddi_iopb_alloc\fR(9F),
\fBscsi_alloc_consistent_buf\fR(9F), \fBscsi_free_consistent_buf\fR(9F),
\fBscsi_pktalloc\fR(9F), \fBscsi_resalloc\fR(9F), \fBscsi_pkt\fR(9S)
.sp
.LP
\fIWriting Device Drivers\fR
.SH NOTES
.sp
.LP
The \fBget_pktiopb()\fR and \fBfree_pktiopb()\fR functions are obsolete and
will be discontinued in a future release. These functions have been replaced
by, respectively, \fBscsi_alloc_consistent_buf\fR(9F) and
\fBscsi_free_consistent_buf\fR(9F).
.sp
.LP
The \fBget_pktiopb()\fR function uses scarce resources. For this reason and its
obsolescence (see above), its use is discouraged.