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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (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]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 1996,1999-2000 by Sun Microsystems, Inc.
* All rights reserved.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* Main Transport Routine for DADA.
*
*/
#include <sys/dada/dada.h>
#include <sys/thread.h>
#define A_TO_TRAN(ap) ((ap)->a_hba_tran)
#define P_TO_TRAN(pkt) ((pkt)->pkt_address.a_hba_tran)
#define P_TO_ADDR(pkt) (&((pkt)->pkt_address))
extern kmutex_t dcd_flag_nointr_mutex;
extern kcondvar_t dcd_flag_nointr_cv;
static void
dcd_flag_nointr_comp(struct dcd_pkt *pkt)
{
mutex_enter(&dcd_flag_nointr_mutex);
pkt->pkt_comp = NULL;
/*
* We need cv_broadcast, because there can be more than
* one thread sleeping on the cv. We will wake all of them.
* The correct one will continue and the reset will again go to
* sleep.
*/
cv_broadcast(&dcd_flag_nointr_cv);
mutex_exit(&dcd_flag_nointr_mutex);
}
int
dcd_transport(struct dcd_pkt *pkt)
{
struct dcd_address *ap = P_TO_ADDR(pkt);
extern int do_polled_io;
int rval;
/*
* Check if we are required to do polled I/O. We can
* get dcd_pkts that don't have the FLAG_NOINTR bit
* set in the pkt_flags. When do_polled_io is set
* we will probably be at a high IPL and not get any
* command completion interrupts. We force polled I/Os
* for such packets and do a callback of the completion
* routine ourselves.
*/
if (!do_polled_io && ((pkt->pkt_flags & FLAG_NOINTR) == 0)) {
return ((*A_TO_TRAN(ap)->tran_start)(ap, pkt));
} else if ((curthread->t_flag & T_INTR_THREAD) || (do_polled_io) ||
(pkt->pkt_flags & FLAG_FORCENOINTR)) {
if (pkt->pkt_flags & FLAG_FORCENOINTR) {
/*
* FLAG_FORCENOINTR means we do not want to rely on
* device interrupts. Set the FLAG_NOINTR
* so the command gets completed in polled mode.
*/
pkt->pkt_flags &= ~FLAG_FORCENOINTR;
pkt->pkt_flags |= FLAG_NOINTR;
}
/*
* If its an interrupt thread or we already have the
* the FLAG_NOINTR flag set, we go ahead and call the
* the hba's start routine directly. We force polling
* only if we have do_polled_io set and FLAG_NOINTR
* not set.
*/
if (!do_polled_io || (pkt->pkt_flags & FLAG_NOINTR)) {
return ((*A_TO_TRAN(ap)->tran_start)(ap, pkt));
} else {
uint_t savef;
void (*savec)();
/*
* save the completion routine and pkt_flags
*/
savef = pkt->pkt_flags;
savec = pkt->pkt_comp;
pkt->pkt_flags |= FLAG_NOINTR;
pkt->pkt_comp = 0;
rval = (*A_TO_TRAN(ap)->tran_start)(ap, pkt);
/*
* Restore the pkt_completion routine
* and pkt flags and call the completion
* routine.
*/
pkt->pkt_comp = savec;
pkt->pkt_flags = savef;
(*pkt->pkt_comp)(pkt);
return (rval);
}
} else {
uint_t savef;
void (*savec)();
int status;
savef = pkt->pkt_flags;
savec = pkt->pkt_comp;
pkt->pkt_comp = dcd_flag_nointr_comp;
pkt->pkt_flags &= ~FLAG_NOINTR;
pkt->pkt_flags |= FLAG_IMMEDIATE_CB;
if ((status = (*A_TO_TRAN(ap)->tran_start)(ap, pkt)) ==
TRAN_ACCEPT) {
mutex_enter(& dcd_flag_nointr_mutex);
while (pkt->pkt_comp != NULL) {
cv_wait(&dcd_flag_nointr_cv,
&dcd_flag_nointr_mutex);
}
mutex_exit(&dcd_flag_nointr_mutex);
}
pkt->pkt_flags = savef;
pkt->pkt_comp = savec;
return (status);
}
}
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