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freebsd/sys/vm/vm_swap.c
Julian Elischer 53ac6efbd8 OK, that's it..
That's EVERY SINGLE driver that has an entry in conf.c..
my next trick will be to define cdevsw[] and bdevsw[]
as empty arrays and remove all those DAMNED defines as well..

Each of these drivers has a SYSINIT linker set entry
that comes in very early.. and asks teh driver to add it's own
entry to the two devsw[] tables.

some slight reworking of the commits from yesterday (added the SYSINIT
stuff and some usually wrong but token DEVFS entries to all these
devices.

BTW does anyone know where the 'ata' entries in conf.c actually reside?
seems we don't actually have a 'ataopen() etc...

If you want to add a new device in conf.c
please  make sure I know
so I can keep it up to date too..

as before, this is all dependent on #if defined(JREMOD)
(and #ifdef DEVFS in parts)
1995-11-29 10:49:16 +00:00

307 lines
7.4 KiB
C

/*
* Copyright (c) 1982, 1986, 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* 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 University of
* California, Berkeley and its contributors.
* 4. 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.
*
* @(#)vm_swap.c 8.5 (Berkeley) 2/17/94
* $Id: vm_swap.c,v 1.25 1995/11/20 12:19:14 phk Exp $
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sysproto.h>
#include <sys/buf.h>
#include <sys/conf.h>
#include <sys/proc.h>
#include <sys/namei.h>
#include <sys/dmap.h> /* XXX */
#include <sys/vnode.h>
#include <sys/file.h>
#include <sys/rlist.h>
#include <vm/vm.h>
#include <miscfs/specfs/specdev.h>
#ifdef JREMOD
#include <sys/kernel.h>
#ifdef DEVFS
#include <sys/devfsext.h>
#endif /*DEVFS*/
#define CDEV_MAJOR 4
#define BDEV_MAJOR 1
#endif /*JREMOD */
/*
* Indirect driver for multi-controller paging.
*/
#ifndef NSWAPDEV
#define NSWAPDEV 4
#endif
static struct swdevt should_be_malloced[NSWAPDEV];
static struct swdevt *swdevt = should_be_malloced;
struct vnode *swapdev_vp;
int nswap; /* first block after the interleaved devs */
static int nswdev = NSWAPDEV;
int vm_swap_size;
void
swstrategy(bp)
register struct buf *bp;
{
int sz, off, seg, index;
register struct swdevt *sp;
struct vnode *vp;
sz = howmany(bp->b_bcount, DEV_BSIZE);
if (nswdev > 1) {
off = bp->b_blkno % dmmax;
if (off + sz > dmmax) {
bp->b_error = EINVAL;
bp->b_flags |= B_ERROR;
biodone(bp);
return;
}
seg = bp->b_blkno / dmmax;
index = seg % nswdev;
seg /= nswdev;
bp->b_blkno = seg * dmmax + off;
} else
index = 0;
sp = &swdevt[index];
if (bp->b_blkno + sz > sp->sw_nblks) {
bp->b_error = EINVAL;
bp->b_flags |= B_ERROR;
biodone(bp);
return;
}
bp->b_dev = sp->sw_dev;
if (sp->sw_vp == NULL) {
bp->b_error = ENODEV;
bp->b_flags |= B_ERROR;
biodone(bp);
return;
}
VHOLD(sp->sw_vp);
if ((bp->b_flags & B_READ) == 0) {
vp = bp->b_vp;
if (vp) {
vp->v_numoutput--;
if ((vp->v_flag & VBWAIT) && vp->v_numoutput <= 0) {
vp->v_flag &= ~VBWAIT;
wakeup(&vp->v_numoutput);
}
}
sp->sw_vp->v_numoutput++;
}
if (bp->b_vp != NULL)
pbrelvp(bp);
bp->b_vp = sp->sw_vp;
VOP_STRATEGY(bp);
}
/*
* System call swapon(name) enables swapping on device name,
* which must be in the swdevsw. Return EBUSY
* if already swapping on this device.
*/
#ifndef _SYS_SYSPROTO_H_
struct swapon_args {
char *name;
};
#endif
/* ARGSUSED */
int
swapon(p, uap, retval)
struct proc *p;
struct swapon_args *uap;
int *retval;
{
register struct vnode *vp;
dev_t dev;
struct nameidata nd;
int error;
error = suser(p->p_ucred, &p->p_acflag);
if (error)
return (error);
NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, uap->name, p);
error = namei(&nd);
if (error)
return (error);
vp = nd.ni_vp;
switch (vp->v_type) {
case VBLK:
dev = (dev_t) vp->v_rdev;
if (major(dev) >= nblkdev) {
error = ENXIO;
break;
}
error = swaponvp(p, vp, dev, 0);
break;
case VCHR:
/*
* For now, we disallow swapping to regular files.
* It requires logical->physcal block translation
* support in the swap pager before it will work.
*/
error = ENOTBLK;
break;
#if 0
error = VOP_GETATTR(vp, &attr, p->p_ucred, p);
if (!error)
error = swaponvp(p, vp, NODEV, attr.va_size / DEV_BSIZE);
break;
#endif
default:
error = EINVAL;
break;
}
if (error)
vrele(vp);
return (error);
}
/*
* Swfree(index) frees the index'th portion of the swap map.
* Each of the nswdev devices provides 1/nswdev'th of the swap
* space, which is laid out with blocks of dmmax pages circularly
* among the devices.
*/
int
swaponvp(p, vp, dev, nblks)
struct proc *p;
struct vnode *vp;
dev_t dev;
u_long nblks;
{
int index;
register struct swdevt *sp;
register swblk_t vsbase;
register long blk;
swblk_t dvbase;
int error;
for (sp = swdevt, index = 0 ; index < nswdev; index++, sp++) {
if (sp->sw_vp == vp)
return EBUSY;
if (!sp->sw_vp)
goto found;
}
return EINVAL;
found:
if (dev != NODEV && (major(dev) >= nblkdev))
return (ENXIO);
error = VOP_OPEN(vp, FREAD | FWRITE, p->p_ucred, p);
if (error)
return (error);
if (nblks == 0 && (bdevsw[major(dev)].d_psize == 0 ||
(nblks = (*bdevsw[major(dev)].d_psize) (dev)) == -1)) {
(void) VOP_CLOSE(vp, FREAD | FWRITE, p->p_ucred, p);
return (ENXIO);
}
if (nblks == 0) {
(void) VOP_CLOSE(vp, FREAD | FWRITE, p->p_ucred, p);
return (ENXIO);
}
sp->sw_vp = vp;
sp->sw_dev = dev;
sp->sw_flags |= SW_FREED;
sp->sw_nblks = nblks;
if (nblks * nswdev > nswap)
nswap = (nblks+1) * nswdev;
for (dvbase = dmmax; dvbase < nblks; dvbase += dmmax) {
blk = min(nblks - dvbase,dmmax);
vsbase = index * dmmax + dvbase * nswdev;
rlist_free(&swaplist, vsbase, vsbase + blk - 1);
vm_swap_size += blk;
}
if (!swapdev_vp && bdevvp(swapdev, &swapdev_vp))
panic("Cannot get vnode for swapdev");
return (0);
}
#ifdef JREMOD
struct bdevsw sw_bdevsw =
{ noopen, noclose, swstrategy, noioc, /*1*/
nodump, zerosize, 0 };
struct cdevsw sw_cdevsw =
{ nullopen, nullclose, rawread, rawwrite, /*4*/
noioc, nostop, noreset, nodevtotty,/* swap */
noselect, nommap, swstrategy };
static sw_devsw_installed = 0;
static void sw_drvinit(void *unused)
{
dev_t dev;
dev_t dev_chr;
if( ! sw_devsw_installed ) {
dev = makedev(CDEV_MAJOR,0);
cdevsw_add(&dev,&sw_cdevsw,NULL);
dev_chr = dev;
dev = makedev(BDEV_MAJOR,0);
bdevsw_add(&dev,&sw_bdevsw,NULL);
sw_devsw_installed = 1;
#ifdef DEVFS
{
int x;
/* default for a simple device with no probe routine (usually delete this) */
x=devfs_add_devsw(
/* path name devsw minor type uid gid perm*/
"/", "rsw", major(dev_chr), 0, DV_CHR, 0, 0, 0600);
x=devfs_add_devsw(
"/", "sw", major(dev), 0, DV_BLK, 0, 0, 0600);
}
}
#endif
}
SYSINIT(swdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,sw_drvinit,NULL)
#endif /* JREMOD */