NetBSD/sys/dev/scsipi/scsi_base.c
bouyer 80620a83a7 Improve handling of memory shortage, to fix problems like:
sd3(mpt0:0:1:0): unable to allocate scsipi_xfer
sd3: not queued, error 12
Havard Eidnes's analysis of this problem is that the scsipi_xfer pool is
competing for resources with other pools, including the the inode and vnode
pools which can grow quite large.

*_scsipi_cmd(): don't biodone the buffer if scsipi_make_xs() fails, let the
   caller deal with the problem
start function of block devices drivers: dequeue the buffer after the
   scsipi_command() call. If scsipi_command() fails with ENOMEM don't dequeue
   the buffer, and schedule a callout to call the start function after
   some delay.
scsipi_init(): prime the scsipi_xfer_pool with one page. This ensure that
   there is always some scsipi_xfer to play with. If scsipi_command() fails
   because of pool_get(), we're sure there will be resources available later,
   when the pending commands have completed.

Reviewed by Jason Thorpe and Havard Eidnes.
Todo: remove the "unable to allocate scsipi_xfer" and "not queued, error %d"
printfs, but I choose to keep them for now, to help make sure the code does
what it should.
2004-08-27 20:37:28 +00:00

145 lines
4.6 KiB
C

/* $NetBSD: scsi_base.c,v 1.80 2004/08/27 20:37:28 bouyer Exp $ */
/*-
* Copyright (c) 1998 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Charles M. Hannum.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: scsi_base.c,v 1.80 2004/08/27 20:37:28 bouyer Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/buf.h>
#include <sys/uio.h>
#include <sys/malloc.h>
#include <sys/errno.h>
#include <sys/device.h>
#include <sys/proc.h>
#include <dev/scsipi/scsipi_all.h>
#include <dev/scsipi/scsi_all.h>
#include <dev/scsipi/scsi_disk.h>
#include <dev/scsipi/scsiconf.h>
#include <dev/scsipi/scsipi_base.h>
/*
* Do a scsi operation, asking a device to run as SCSI-II if it can.
*/
int
scsi_change_def(struct scsipi_periph *periph, int flags)
{
struct scsi_changedef scsipi_cmd;
memset(&scsipi_cmd, 0, sizeof(scsipi_cmd));
scsipi_cmd.opcode = SCSI_CHANGE_DEFINITION;
scsipi_cmd.how = SC_SCSI_2;
return (scsipi_command(periph,
(struct scsipi_generic *) &scsipi_cmd, sizeof(scsipi_cmd),
0, 0, SCSIPIRETRIES, 100000, NULL, flags));
}
/*
* ask the scsi driver to perform a command for us.
* tell it where to read/write the data, and how
* long the data is supposed to be. If we have a buf
* to associate with the transfer, we need that too.
*/
int
scsi_scsipi_cmd(struct scsipi_periph *periph, struct scsipi_generic *scsipi_cmd,
int cmdlen, void *data, size_t datalen, int retries, int timeout,
struct buf *bp, int flags)
{
struct scsipi_xfer *xs;
int error;
SC_DEBUG(periph, SCSIPI_DB2, ("scsi_scsipi_cmd\n"));
#ifdef DIAGNOSTIC
if (bp != NULL && (flags & XS_CTL_ASYNC) == 0)
panic("scsi_scsipi_cmd: buffer without async");
#endif
if ((xs = scsipi_make_xs(periph, scsipi_cmd, cmdlen, data,
datalen, retries, timeout, bp, flags)) == NULL) {
/* let the caller deal with this */
return (ENOMEM);
}
/*
* Set the LUN in the CDB if we have an older device. We also
* set it for more modern SCSI-2 devices "just in case".
*/
if (periph->periph_version <= 2)
xs->cmd->bytes[0] |=
((periph->periph_lun << SCSI_CMD_LUN_SHIFT) &
SCSI_CMD_LUN_MASK);
if ((error = scsipi_execute_xs(xs)) == EJUSTRETURN)
return (0);
return (error);
}
/*
* Utility routines often used in SCSI stuff
*/
/*
* Print out the periph's address info.
*/
void
scsi_print_addr(struct scsipi_periph *periph)
{
struct scsipi_channel *chan = periph->periph_channel;
struct scsipi_adapter *adapt = chan->chan_adapter;
printf("%s(%s:%d:%d:%d): ", periph->periph_dev != NULL ?
periph->periph_dev->dv_xname : "probe",
adapt->adapt_dev->dv_xname,
chan->chan_channel, periph->periph_target,
periph->periph_lun);
}
/*
* Kill off all pending xfers for a periph.
*
* Must be called at splbio().
*/
void
scsi_kill_pending(struct scsipi_periph *periph)
{
}