514 lines
12 KiB
C
514 lines
12 KiB
C
/* $NetBSD: md.c,v 1.50 2007/07/29 12:50:18 ad Exp $ */
|
|
|
|
/*
|
|
* Copyright (c) 1995 Gordon W. Ross, Leo Weppelman.
|
|
* 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. The name of the author may not be used to endorse or promote products
|
|
* derived from this software without specific prior written permission.
|
|
* 4. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by
|
|
* Gordon W. Ross and Leo Weppelman.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
|
|
*/
|
|
|
|
/*
|
|
* This implements a general-purpose memory-disk.
|
|
* See md.h for notes on the config types.
|
|
*
|
|
* Note that this driver provides the same functionality
|
|
* as the MFS filesystem hack, but this is better because
|
|
* you can use this for any filesystem type you'd like!
|
|
*
|
|
* Credit for most of the kmem ramdisk code goes to:
|
|
* Leo Weppelman (atari) and Phil Nelson (pc532)
|
|
* Credit for the ideas behind the "user space memory" code goes
|
|
* to the authors of the MFS implementation.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__KERNEL_RCSID(0, "$NetBSD: md.c,v 1.50 2007/07/29 12:50:18 ad Exp $");
|
|
|
|
#include "opt_md.h"
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/buf.h>
|
|
#include <sys/bufq.h>
|
|
#include <sys/device.h>
|
|
#include <sys/disk.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/conf.h>
|
|
#include <sys/disklabel.h>
|
|
|
|
#include <uvm/uvm_extern.h>
|
|
|
|
#include <dev/md.h>
|
|
|
|
/*
|
|
* The user-space functionality is included by default.
|
|
* Use `options MEMORY_DISK_SERVER=0' to turn it off.
|
|
*/
|
|
#ifndef MEMORY_DISK_SERVER
|
|
#error MEMORY_DISK_SERVER should be defined by opt_md.h
|
|
#endif /* MEMORY_DISK_SERVER */
|
|
|
|
/*
|
|
* We should use the raw partition for ioctl.
|
|
*/
|
|
#define MD_MAX_UNITS 0x10
|
|
#define MD_UNIT(unit) DISKUNIT(unit)
|
|
|
|
/* autoconfig stuff... */
|
|
|
|
struct md_softc {
|
|
struct device sc_dev; /* REQUIRED first entry */
|
|
struct disk sc_dkdev; /* hook for generic disk handling */
|
|
struct md_conf sc_md;
|
|
struct bufq_state *sc_buflist;
|
|
};
|
|
/* shorthand for fields in sc_md: */
|
|
#define sc_addr sc_md.md_addr
|
|
#define sc_size sc_md.md_size
|
|
#define sc_type sc_md.md_type
|
|
|
|
void mdattach(int);
|
|
|
|
static void md_attach(struct device *, struct device *, void *);
|
|
|
|
static dev_type_open(mdopen);
|
|
static dev_type_close(mdclose);
|
|
static dev_type_read(mdread);
|
|
static dev_type_write(mdwrite);
|
|
static dev_type_ioctl(mdioctl);
|
|
static dev_type_strategy(mdstrategy);
|
|
static dev_type_size(mdsize);
|
|
|
|
const struct bdevsw md_bdevsw = {
|
|
mdopen, mdclose, mdstrategy, mdioctl, nodump, mdsize, D_DISK
|
|
};
|
|
|
|
const struct cdevsw md_cdevsw = {
|
|
mdopen, mdclose, mdread, mdwrite, mdioctl,
|
|
nostop, notty, nopoll, nommap, nokqfilter, D_DISK
|
|
};
|
|
|
|
static struct dkdriver mddkdriver = { mdstrategy, NULL };
|
|
|
|
static int ramdisk_ndevs;
|
|
static void *ramdisk_devs[MD_MAX_UNITS];
|
|
|
|
/*
|
|
* This is called if we are configured as a pseudo-device
|
|
*/
|
|
void
|
|
mdattach(int n)
|
|
{
|
|
struct md_softc *sc;
|
|
int i;
|
|
|
|
#ifdef DIAGNOSTIC
|
|
if (ramdisk_ndevs) {
|
|
aprint_error("ramdisk: multiple attach calls?\n");
|
|
return;
|
|
}
|
|
#endif
|
|
|
|
/* XXX: Are we supposed to provide a default? */
|
|
if (n <= 1)
|
|
n = 1;
|
|
if (n > MD_MAX_UNITS)
|
|
n = MD_MAX_UNITS;
|
|
ramdisk_ndevs = n;
|
|
|
|
/* Attach as if by autoconfig. */
|
|
for (i = 0; i < n; i++) {
|
|
|
|
sc = malloc(sizeof(*sc), M_DEVBUF, M_NOWAIT|M_ZERO);
|
|
if (!sc) {
|
|
aprint_error("ramdisk: malloc for attach failed!\n");
|
|
return;
|
|
}
|
|
ramdisk_devs[i] = sc;
|
|
sc->sc_dev.dv_unit = i;
|
|
snprintf(sc->sc_dev.dv_xname, sizeof(sc->sc_dev.dv_xname),
|
|
"md%d", i);
|
|
md_attach(NULL, &sc->sc_dev, NULL);
|
|
}
|
|
}
|
|
|
|
static void
|
|
md_attach(struct device *parent, struct device *self,
|
|
void *aux)
|
|
{
|
|
struct md_softc *sc = (struct md_softc *)self;
|
|
|
|
bufq_alloc(&sc->sc_buflist, "fcfs", 0);
|
|
|
|
/* XXX - Could accept aux info here to set the config. */
|
|
#ifdef MEMORY_DISK_HOOKS
|
|
/*
|
|
* This external function might setup a pre-loaded disk.
|
|
* All it would need to do is setup the md_conf struct.
|
|
* See sys/dev/md_root.c for an example.
|
|
*/
|
|
md_attach_hook(device_unit(&sc->sc_dev), &sc->sc_md);
|
|
#endif
|
|
|
|
/*
|
|
* Initialize and attach the disk structure.
|
|
*/
|
|
sc->sc_dkdev.dk_driver = &mddkdriver;
|
|
sc->sc_dkdev.dk_name = sc->sc_dev.dv_xname;
|
|
disk_attach(&sc->sc_dkdev);
|
|
}
|
|
|
|
/*
|
|
* operational routines:
|
|
* open, close, read, write, strategy,
|
|
* ioctl, dump, size
|
|
*/
|
|
|
|
#if MEMORY_DISK_SERVER
|
|
static int md_server_loop(struct md_softc *sc);
|
|
static int md_ioctl_server(struct md_softc *sc, struct md_conf *umd,
|
|
struct lwp *l);
|
|
#endif /* MEMORY_DISK_SERVER */
|
|
static int md_ioctl_kalloc(struct md_softc *sc, struct md_conf *umd,
|
|
struct lwp *l);
|
|
|
|
static int
|
|
mdsize(dev_t dev)
|
|
{
|
|
int unit;
|
|
struct md_softc *sc;
|
|
|
|
unit = MD_UNIT(dev);
|
|
if (unit >= ramdisk_ndevs)
|
|
return 0;
|
|
sc = ramdisk_devs[unit];
|
|
if (sc == NULL)
|
|
return 0;
|
|
|
|
if (sc->sc_type == MD_UNCONFIGURED)
|
|
return 0;
|
|
|
|
return (sc->sc_size >> DEV_BSHIFT);
|
|
}
|
|
|
|
static int
|
|
mdopen(dev_t dev, int flag, int fmt, struct lwp *l)
|
|
{
|
|
int unit;
|
|
struct md_softc *sc;
|
|
|
|
unit = MD_UNIT(dev);
|
|
if (unit >= ramdisk_ndevs)
|
|
return ENXIO;
|
|
sc = ramdisk_devs[unit];
|
|
if (sc == NULL)
|
|
return ENXIO;
|
|
|
|
/*
|
|
* The raw partition is used for ioctl to configure.
|
|
*/
|
|
if (DISKPART(dev) == RAW_PART)
|
|
return 0;
|
|
|
|
#ifdef MEMORY_DISK_HOOKS
|
|
/* Call the open hook to allow loading the device. */
|
|
md_open_hook(unit, &sc->sc_md);
|
|
#endif
|
|
|
|
/*
|
|
* This is a normal, "slave" device, so
|
|
* enforce initialized.
|
|
*/
|
|
if (sc->sc_type == MD_UNCONFIGURED)
|
|
return ENXIO;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
mdclose(dev_t dev, int flag, int fmt, struct lwp *l)
|
|
{
|
|
int unit;
|
|
|
|
unit = MD_UNIT(dev);
|
|
|
|
if (unit >= ramdisk_ndevs)
|
|
return ENXIO;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
mdread(dev_t dev, struct uio *uio, int flags)
|
|
{
|
|
int unit;
|
|
struct md_softc *sc;
|
|
|
|
unit = MD_UNIT(dev);
|
|
|
|
if (unit >= ramdisk_ndevs)
|
|
return ENXIO;
|
|
|
|
sc = ramdisk_devs[unit];
|
|
|
|
if (sc->sc_type == MD_UNCONFIGURED)
|
|
return ENXIO;
|
|
|
|
return (physio(mdstrategy, NULL, dev, B_READ, minphys, uio));
|
|
}
|
|
|
|
static int
|
|
mdwrite(dev_t dev, struct uio *uio, int flags)
|
|
{
|
|
int unit;
|
|
struct md_softc *sc;
|
|
|
|
unit = MD_UNIT(dev);
|
|
|
|
if (unit >= ramdisk_ndevs)
|
|
return ENXIO;
|
|
|
|
sc = ramdisk_devs[unit];
|
|
|
|
if (sc->sc_type == MD_UNCONFIGURED)
|
|
return ENXIO;
|
|
|
|
return (physio(mdstrategy, NULL, dev, B_WRITE, minphys, uio));
|
|
}
|
|
|
|
/*
|
|
* Handle I/O requests, either directly, or
|
|
* by passing them to the server process.
|
|
*/
|
|
static void
|
|
mdstrategy(struct buf *bp)
|
|
{
|
|
int unit;
|
|
struct md_softc *sc;
|
|
void * addr;
|
|
size_t off, xfer;
|
|
|
|
unit = MD_UNIT(bp->b_dev);
|
|
sc = ramdisk_devs[unit];
|
|
|
|
if (sc->sc_type == MD_UNCONFIGURED) {
|
|
bp->b_error = ENXIO;
|
|
goto done;
|
|
}
|
|
|
|
switch (sc->sc_type) {
|
|
#if MEMORY_DISK_SERVER
|
|
case MD_UMEM_SERVER:
|
|
/* Just add this job to the server's queue. */
|
|
BUFQ_PUT(sc->sc_buflist, bp);
|
|
wakeup((void *)sc);
|
|
/* see md_server_loop() */
|
|
/* no biodone in this case */
|
|
return;
|
|
#endif /* MEMORY_DISK_SERVER */
|
|
|
|
case MD_KMEM_FIXED:
|
|
case MD_KMEM_ALLOCATED:
|
|
/* These are in kernel space. Access directly. */
|
|
bp->b_resid = bp->b_bcount;
|
|
off = (bp->b_blkno << DEV_BSHIFT);
|
|
if (off >= sc->sc_size) {
|
|
if (bp->b_flags & B_READ)
|
|
break; /* EOF */
|
|
goto set_eio;
|
|
}
|
|
xfer = bp->b_resid;
|
|
if (xfer > (sc->sc_size - off))
|
|
xfer = (sc->sc_size - off);
|
|
addr = (char *)sc->sc_addr + off;
|
|
if (bp->b_flags & B_READ)
|
|
memcpy(bp->b_data, addr, xfer);
|
|
else
|
|
memcpy(addr, bp->b_data, xfer);
|
|
bp->b_resid -= xfer;
|
|
break;
|
|
|
|
default:
|
|
bp->b_resid = bp->b_bcount;
|
|
set_eio:
|
|
bp->b_error = EIO;
|
|
break;
|
|
}
|
|
done:
|
|
biodone(bp);
|
|
}
|
|
|
|
static int
|
|
mdioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
|
|
{
|
|
int unit;
|
|
struct md_softc *sc;
|
|
struct md_conf *umd;
|
|
|
|
unit = MD_UNIT(dev);
|
|
sc = ramdisk_devs[unit];
|
|
|
|
/* If this is not the raw partition, punt! */
|
|
if (DISKPART(dev) != RAW_PART)
|
|
return ENOTTY;
|
|
|
|
umd = (struct md_conf *)data;
|
|
switch (cmd) {
|
|
case MD_GETCONF:
|
|
*umd = sc->sc_md;
|
|
return 0;
|
|
|
|
case MD_SETCONF:
|
|
/* Can only set it once. */
|
|
if (sc->sc_type != MD_UNCONFIGURED)
|
|
break;
|
|
switch (umd->md_type) {
|
|
case MD_KMEM_ALLOCATED:
|
|
return md_ioctl_kalloc(sc, umd, l);
|
|
#if MEMORY_DISK_SERVER
|
|
case MD_UMEM_SERVER:
|
|
return md_ioctl_server(sc, umd, l);
|
|
#endif /* MEMORY_DISK_SERVER */
|
|
default:
|
|
break;
|
|
}
|
|
break;
|
|
}
|
|
return EINVAL;
|
|
}
|
|
|
|
/*
|
|
* Handle ioctl MD_SETCONF for (sc_type == MD_KMEM_ALLOCATED)
|
|
* Just allocate some kernel memory and return.
|
|
*/
|
|
static int
|
|
md_ioctl_kalloc(struct md_softc *sc, struct md_conf *umd,
|
|
struct lwp *l)
|
|
{
|
|
vaddr_t addr;
|
|
vsize_t size;
|
|
|
|
/* Sanity check the size. */
|
|
size = umd->md_size;
|
|
addr = uvm_km_alloc(kernel_map, size, 0, UVM_KMF_WIRED|UVM_KMF_ZERO);
|
|
if (!addr)
|
|
return ENOMEM;
|
|
|
|
/* This unit is now configured. */
|
|
sc->sc_addr = (void *)addr; /* kernel space */
|
|
sc->sc_size = (size_t)size;
|
|
sc->sc_type = MD_KMEM_ALLOCATED;
|
|
return 0;
|
|
}
|
|
|
|
#if MEMORY_DISK_SERVER
|
|
|
|
/*
|
|
* Handle ioctl MD_SETCONF for (sc_type == MD_UMEM_SERVER)
|
|
* Set config, then become the I/O server for this unit.
|
|
*/
|
|
static int
|
|
md_ioctl_server(struct md_softc *sc, struct md_conf *umd,
|
|
struct lwp *l)
|
|
{
|
|
vaddr_t end;
|
|
int error;
|
|
|
|
/* Sanity check addr, size. */
|
|
end = (vaddr_t) ((char *)umd->md_addr + umd->md_size);
|
|
|
|
if ((end >= VM_MAXUSER_ADDRESS) ||
|
|
(end < ((vaddr_t) umd->md_addr)) )
|
|
return EINVAL;
|
|
|
|
/* This unit is now configured. */
|
|
sc->sc_addr = umd->md_addr; /* user space */
|
|
sc->sc_size = umd->md_size;
|
|
sc->sc_type = MD_UMEM_SERVER;
|
|
|
|
/* Become the server daemon */
|
|
error = md_server_loop(sc);
|
|
|
|
/* This server is now going away! */
|
|
sc->sc_type = MD_UNCONFIGURED;
|
|
sc->sc_addr = 0;
|
|
sc->sc_size = 0;
|
|
|
|
return (error);
|
|
}
|
|
|
|
static int md_sleep_pri = PWAIT | PCATCH;
|
|
|
|
static int
|
|
md_server_loop(struct md_softc *sc)
|
|
{
|
|
struct buf *bp;
|
|
void *addr; /* user space address */
|
|
size_t off; /* offset into "device" */
|
|
size_t xfer; /* amount to transfer */
|
|
int error;
|
|
|
|
for (;;) {
|
|
/* Wait for some work to arrive. */
|
|
while ((bp = BUFQ_GET(sc->sc_buflist)) == NULL) {
|
|
error = tsleep((void *)sc, md_sleep_pri, "md_idle", 0);
|
|
if (error)
|
|
return error;
|
|
}
|
|
|
|
/* Do the transfer to/from user space. */
|
|
error = 0;
|
|
bp->b_resid = bp->b_bcount;
|
|
off = (bp->b_blkno << DEV_BSHIFT);
|
|
if (off >= sc->sc_size) {
|
|
if (bp->b_flags & B_READ)
|
|
goto done; /* EOF (not an error) */
|
|
error = EIO;
|
|
goto done;
|
|
}
|
|
xfer = bp->b_resid;
|
|
if (xfer > (sc->sc_size - off))
|
|
xfer = (sc->sc_size - off);
|
|
addr = (char *)sc->sc_addr + off;
|
|
if (bp->b_flags & B_READ)
|
|
error = copyin(addr, bp->b_data, xfer);
|
|
else
|
|
error = copyout(bp->b_data, addr, xfer);
|
|
if (!error)
|
|
bp->b_resid -= xfer;
|
|
|
|
done:
|
|
if (error) {
|
|
bp->b_error = error;
|
|
}
|
|
biodone(bp);
|
|
}
|
|
}
|
|
#endif /* MEMORY_DISK_SERVER */
|