404 lines
9.9 KiB
C
404 lines
9.9 KiB
C
/* $NetBSD: subr_bufq.c,v 1.27 2019/02/17 23:17:41 bad Exp $ */
|
|
/* NetBSD: subr_disk.c,v 1.70 2005/08/20 12:00:01 yamt Exp $ */
|
|
|
|
/*-
|
|
* Copyright (c) 1996, 1997, 1999, 2000 The NetBSD Foundation, Inc.
|
|
* All rights reserved.
|
|
*
|
|
* This code is derived from software contributed to The NetBSD Foundation
|
|
* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
|
|
* NASA Ames Research Center.
|
|
*
|
|
* 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.
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
/*
|
|
* Copyright (c) 1982, 1986, 1988, 1993
|
|
* The Regents of the University of California. All rights reserved.
|
|
* (c) UNIX System Laboratories, Inc.
|
|
* All or some portions of this file are derived from material licensed
|
|
* to the University of California by American Telephone and Telegraph
|
|
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
|
|
* the permission of UNIX System Laboratories, Inc.
|
|
*
|
|
* 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. Neither the name of the University 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 REGENTS 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 REGENTS 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.
|
|
*
|
|
* @(#)ufs_disksubr.c 8.5 (Berkeley) 1/21/94
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__KERNEL_RCSID(0, "$NetBSD: subr_bufq.c,v 1.27 2019/02/17 23:17:41 bad Exp $");
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/buf.h>
|
|
#include <sys/bufq.h>
|
|
#include <sys/bufq_impl.h>
|
|
#include <sys/kmem.h>
|
|
#include <sys/sysctl.h>
|
|
#include <sys/module.h>
|
|
|
|
#define STRAT_MATCH(id, bs) (strcmp((id), (bs)->bs_name) == 0)
|
|
|
|
static void sysctl_kern_bufq_strategies_setup(struct sysctllog **);
|
|
static SLIST_HEAD(, bufq_strat) bufq_strat_list =
|
|
SLIST_HEAD_INITIALIZER(bufq_strat_list);
|
|
|
|
static kmutex_t bufq_mutex;
|
|
|
|
static struct sysctllog *sysctllog;
|
|
|
|
void
|
|
bufq_init(void)
|
|
{
|
|
|
|
mutex_init(&bufq_mutex, MUTEX_DEFAULT, IPL_NONE);
|
|
sysctl_kern_bufq_strategies_setup(&sysctllog);
|
|
}
|
|
|
|
int
|
|
bufq_register(struct bufq_strat *bs)
|
|
{
|
|
|
|
mutex_enter(&bufq_mutex);
|
|
SLIST_INSERT_HEAD(&bufq_strat_list, bs, bs_next);
|
|
bs->bs_refcnt = 0;
|
|
mutex_exit(&bufq_mutex);
|
|
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
bufq_unregister(struct bufq_strat *bs)
|
|
{
|
|
|
|
mutex_enter(&bufq_mutex);
|
|
if (bs->bs_refcnt != 0) {
|
|
mutex_exit(&bufq_mutex);
|
|
return EBUSY;
|
|
}
|
|
SLIST_REMOVE(&bufq_strat_list, bs, bufq_strat, bs_next);
|
|
mutex_exit(&bufq_mutex);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Create a device buffer queue.
|
|
*/
|
|
int
|
|
bufq_alloc(struct bufq_state **bufqp, const char *strategy, int flags)
|
|
{
|
|
struct bufq_strat *bsp, *it;
|
|
struct bufq_state *bufq;
|
|
int error = 0;
|
|
u_int gen;
|
|
bool found_exact;
|
|
char strategy_module_name[MAXPATHLEN];
|
|
|
|
KASSERT((flags & BUFQ_EXACT) == 0 || strategy != BUFQ_STRAT_ANY);
|
|
|
|
switch (flags & BUFQ_SORT_MASK) {
|
|
case BUFQ_SORT_RAWBLOCK:
|
|
case BUFQ_SORT_CYLINDER:
|
|
break;
|
|
case 0:
|
|
/*
|
|
* for strategies which don't care about block numbers.
|
|
* eg. fcfs
|
|
*/
|
|
flags |= BUFQ_SORT_RAWBLOCK;
|
|
break;
|
|
default:
|
|
panic("bufq_alloc: sort out of range");
|
|
}
|
|
|
|
/*
|
|
* select strategy.
|
|
* if a strategy specified by flags is found, use it.
|
|
* otherwise, select one with the largest bs_prio.
|
|
*/
|
|
mutex_enter(&bufq_mutex);
|
|
do {
|
|
gen = module_gen;
|
|
bsp = NULL;
|
|
found_exact = false;
|
|
|
|
SLIST_FOREACH(it, &bufq_strat_list, bs_next) {
|
|
if (strategy != BUFQ_STRAT_ANY &&
|
|
STRAT_MATCH(strategy, (it))) {
|
|
bsp = it;
|
|
found_exact = true;
|
|
break;
|
|
}
|
|
if (bsp == NULL || (it)->bs_prio > bsp->bs_prio)
|
|
bsp = it;
|
|
}
|
|
if (strategy == BUFQ_STRAT_ANY || found_exact)
|
|
break;
|
|
|
|
/* Try to autoload the bufq strategy module */
|
|
strlcpy(strategy_module_name, "bufq_",
|
|
sizeof(strategy_module_name));
|
|
strlcat(strategy_module_name, strategy,
|
|
sizeof(strategy_module_name));
|
|
mutex_exit(&bufq_mutex);
|
|
(void) module_autoload(strategy_module_name, MODULE_CLASS_BUFQ);
|
|
mutex_enter(&bufq_mutex);
|
|
} while (gen != module_gen);
|
|
|
|
if (bsp == NULL) {
|
|
panic("bufq_alloc: no strategy");
|
|
}
|
|
if (strategy != BUFQ_STRAT_ANY && !found_exact) {
|
|
if ((flags & BUFQ_EXACT)) {
|
|
error = ENOENT;
|
|
mutex_exit(&bufq_mutex);
|
|
goto out;
|
|
}
|
|
#if defined(DEBUG)
|
|
printf("bufq_alloc: '%s' is not available. using '%s'.\n",
|
|
strategy, bsp->bs_name);
|
|
#endif
|
|
}
|
|
#if defined(BUFQ_DEBUG)
|
|
/* XXX aprint? */
|
|
printf("bufq_alloc: using '%s'\n", bsp->bs_name);
|
|
#endif
|
|
|
|
bsp->bs_refcnt++;
|
|
mutex_exit(&bufq_mutex);
|
|
*bufqp = bufq = kmem_zalloc(sizeof(*bufq), KM_SLEEP);
|
|
bufq->bq_flags = flags;
|
|
bufq->bq_strat = bsp;
|
|
(*bsp->bs_initfn)(bufq);
|
|
|
|
out:
|
|
return error;
|
|
}
|
|
|
|
void
|
|
bufq_put(struct bufq_state *bufq, struct buf *bp)
|
|
{
|
|
|
|
(*bufq->bq_put)(bufq, bp);
|
|
}
|
|
|
|
struct buf *
|
|
bufq_get(struct bufq_state *bufq)
|
|
{
|
|
|
|
return (*bufq->bq_get)(bufq, 1);
|
|
}
|
|
|
|
struct buf *
|
|
bufq_peek(struct bufq_state *bufq)
|
|
{
|
|
|
|
return (*bufq->bq_get)(bufq, 0);
|
|
}
|
|
|
|
struct buf *
|
|
bufq_cancel(struct bufq_state *bufq, struct buf *bp)
|
|
{
|
|
|
|
return (*bufq->bq_cancel)(bufq, bp);
|
|
}
|
|
|
|
/*
|
|
* Drain a device buffer queue.
|
|
*/
|
|
void
|
|
bufq_drain(struct bufq_state *bufq)
|
|
{
|
|
struct buf *bp;
|
|
|
|
while ((bp = bufq_get(bufq)) != NULL) {
|
|
bp->b_error = EIO;
|
|
bp->b_resid = bp->b_bcount;
|
|
biodone(bp);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Destroy a device buffer queue.
|
|
*/
|
|
void
|
|
bufq_free(struct bufq_state *bufq)
|
|
{
|
|
|
|
KASSERT(bufq_peek(bufq) == NULL);
|
|
|
|
bufq->bq_fini(bufq);
|
|
|
|
mutex_enter(&bufq_mutex);
|
|
bufq->bq_strat->bs_refcnt--;
|
|
mutex_exit(&bufq_mutex);
|
|
|
|
kmem_free(bufq, sizeof(*bufq));
|
|
}
|
|
|
|
/*
|
|
* get a strategy identifier of a buffer queue.
|
|
*/
|
|
const char *
|
|
bufq_getstrategyname(struct bufq_state *bufq)
|
|
{
|
|
|
|
return bufq->bq_strat->bs_name;
|
|
}
|
|
|
|
/*
|
|
* move all requests on a buffer queue to another.
|
|
*/
|
|
void
|
|
bufq_move(struct bufq_state *dst, struct bufq_state *src)
|
|
{
|
|
struct buf *bp;
|
|
|
|
while ((bp = bufq_get(src)) != NULL) {
|
|
bufq_put(dst, bp);
|
|
}
|
|
}
|
|
|
|
static int
|
|
docopy(char *buf, size_t *bufoffp, size_t buflen,
|
|
const char *datap, size_t datalen)
|
|
{
|
|
int error = 0;
|
|
|
|
if (buf != NULL && datalen > 0) {
|
|
|
|
if (*bufoffp + datalen > buflen) {
|
|
goto out;
|
|
}
|
|
error = copyout(datap, buf + *bufoffp, datalen);
|
|
if (error) {
|
|
goto out;
|
|
}
|
|
}
|
|
out:
|
|
if (error == 0) {
|
|
*bufoffp += datalen;
|
|
}
|
|
|
|
return error;
|
|
}
|
|
|
|
static int
|
|
docopystr(char *buf, size_t *bufoffp, size_t buflen, const char *datap)
|
|
{
|
|
|
|
return docopy(buf, bufoffp, buflen, datap, strlen(datap));
|
|
}
|
|
|
|
static int
|
|
docopynul(char *buf, size_t *bufoffp, size_t buflen)
|
|
{
|
|
|
|
return docopy(buf, bufoffp, buflen, "", 1);
|
|
}
|
|
|
|
/*
|
|
* sysctl function that will print all bufq strategies
|
|
* currently available to the kernel.
|
|
*/
|
|
static int
|
|
sysctl_kern_bufq_strategies(SYSCTLFN_ARGS)
|
|
{
|
|
const struct bufq_strat *bq_strat;
|
|
const char *delim = "";
|
|
size_t off = 0;
|
|
size_t buflen = *oldlenp;
|
|
int error;
|
|
|
|
SLIST_FOREACH(bq_strat, &bufq_strat_list, bs_next) {
|
|
error = docopystr(oldp, &off, buflen, delim);
|
|
if (error) {
|
|
goto out;
|
|
}
|
|
error = docopystr(oldp, &off, buflen, (bq_strat)->bs_name);
|
|
if (error) {
|
|
goto out;
|
|
}
|
|
delim = " ";
|
|
}
|
|
|
|
/* In case there are no registered strategies ... */
|
|
if (off == 0) {
|
|
error = docopystr(oldp, &off, buflen, "NULL");
|
|
if (error) {
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
/* NUL terminate */
|
|
error = docopynul(oldp, &off, buflen);
|
|
out:
|
|
*oldlenp = off;
|
|
return error;
|
|
}
|
|
|
|
static void
|
|
sysctl_kern_bufq_strategies_setup(struct sysctllog **clog)
|
|
{
|
|
const struct sysctlnode *node;
|
|
|
|
node = NULL;
|
|
sysctl_createv(clog, 0, NULL, &node,
|
|
CTLFLAG_PERMANENT,
|
|
CTLTYPE_NODE, "bufq",
|
|
SYSCTL_DESCR("buffer queue subtree"),
|
|
NULL, 0, NULL, 0,
|
|
CTL_KERN, CTL_CREATE, CTL_EOL);
|
|
if (node != NULL) {
|
|
sysctl_createv(clog, 0, NULL, NULL,
|
|
CTLFLAG_PERMANENT,
|
|
CTLTYPE_STRING, "strategies",
|
|
SYSCTL_DESCR("List of bufq strategies present"),
|
|
sysctl_kern_bufq_strategies, 0, NULL, 0,
|
|
CTL_KERN, node->sysctl_num, CTL_CREATE, CTL_EOL);
|
|
}
|
|
}
|