Bochs/bochs/plex86/kernel/host-freebsd.c
Kevin Lawton 0768d01522 Added plex86 directory to bochs. This directory contains the
new experimental stripped-down version of plex86, which is now
  a user-code-only VM.  I ripped out all the fancy stuff in plex86,
  such that under that right conditions, user-code (protection level 3)
  can run at near native speeds inside the plex86 VM.
The general idea is that bochs emulates all the initial real-mode code,
  and guest kernel code (protection level 0).  When it senses the
  right conditions (like the context switches to user-code), a shim
  is called to execute the guest inside the plex86 VM.  All guest-generated
  faults/exceptions are then forwarded back to bochs to be handled in
  the emulator.
Actually, I'm not yet adding the mods to the bochs code (other than
  the shim code which is in a separate file), until I hear that we're
  back in a more development mode with bochs after the 2.0 release.
The plex86 subdirectory is really a separate project.  It's just more
  convenient to co-develop it with bochs for now.  Both projects are
  currently LGPL, but each should be taken to be a separate project,
  and have their own license file.  Plex86 (it's only a kernel driver
  now) could ultimately be used with other projects, as it's modular.
  I talked with Bryce, and we both agreed it's OK to keep plex86 as
  a subdir in bochs for now.
2003-01-01 17:32:06 +00:00

570 lines
13 KiB
C

/*
* plex86: run multiple x86 operating systems concurrently
*
* Copyright (C) 2000 Frank van der Linden (fvdl@wasabisystems.com)
* Copyright (C) 2000 Alexander Langer <alex@big.endian.de>
*
* License as published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#define DIAGNOSTIC 1
#define CDEV_MAJOR 20
#define timer_t __bsd_timer_t
#define write_eflags __freebsd_write_eflags
#define read_eflags __freebsd_read_eflags
/* XXX recheck, which includes are needed */
#include <sys/param.h>
#include <sys/types.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/conf.h>
#include <sys/exec.h>
#include <sys/malloc.h>
#include <sys/syslog.h>
#include <sys/queue.h>
#include <sys/signalvar.h>
#include <sys/mman.h>
#include <sys/kernel.h>
#include <sys/linker.h>
#include <sys/sysproto.h>
#include <sys/module.h>
#include <vm/vm.h>
#include <machine/cpu.h>
#undef timer_t
#undef write_eflags
#undef read_eflags
#include "plex86.h"
#define IN_HOST_SPACE
#include "monitor.h"
static MALLOC_DEFINE(M_PLEX86, "plex86", "Plex86 mem");
static d_open_t plex86_open;
static d_close_t plex86_close;
static d_mmap_t plex86_mmap;
static d_ioctl_t plex86_ioctl;
static unsigned retrieve_phy_pages(Bit32u *, int, void *, unsigned, int);
static vm_t *find_vm(struct proc * p);
static void register_vm(vm_t * vm, struct proc * p);
static void unregister_all(struct proc * p);
static struct cdevsw plex86_cdevsw = {
/* open */ plex86_open,
/* close */ plex86_close,
/* read */ noread,
/* write */ nowrite,
/* ioctl */ plex86_ioctl,
/* poll */ nopoll,
/* mmap */ plex86_mmap,
/* strat */ nostrategy,
/* name */ "plex86",
/* major */ CDEV_MAJOR,
/* dump */ nodump,
/* psize */ nopsize,
/* flags */ 0,
/* bmaj */ -1
};
/* For use with make_dev/destroy_dev */
static dev_t plex86_dev;
static struct plex86_softc {
int sc_open;
} plex86sc;
monitor_pages_t monitor_pages;
/*
* Hash table stuff to maintain proc <-> vm mapping. 23 entries should be
* plenty.. unless someone plans to run more than 23 guest OSs..
*
* Note that a process can only open the device once with this scheme.
*/
LIST_HEAD(plex86_hashhead, plex86_vmentry);
struct plex86_vmentry {
pid_t vm_pid;
vm_t *vm_vm;
LIST_ENTRY(plex86_vmentry) vm_entry;
};
struct plex86_hashhead *plex86_hashtbl;
u_long plex86_hashmask;
#define PLEX86_VMHASHSIZE 23
#define PLEX86_VMHASH(p) ((u_long)((p)->p_pid) & plex86_hashmask)
static int
plex86_open(dev_t dev, int flags, int fmt, struct proc * p)
{
vm_t *vm;
if (suser_xxx(p->p_ucred, p, p->p_acflag) != 0)
return (EPERM);
vm = find_vm(p);
if (vm == NULL) {
vm = malloc(sizeof(vm_t), M_PLEX86, M_WAITOK);
if (vm == NULL)
return EIO;
memset(vm, 0, sizeof(vm_t));
register_vm(vm, p);
plex86sc.sc_open++;
} else
return (EBUSY);
/* Kernel independent device open code. */
hostDeviceOpenInit(vm);
#ifdef FREEBSD_PLEX86_DEBUG
printf("plex86: pid %u opened device, vm %p\n", p->p_pid, vm);
#endif
return (0);
}
int
plex86_close(dev_t dev, int flags, int fmt, struct proc * p)
{
unregister_all(p);
plex86sc.sc_open = 0;
#ifdef FREEBSD_PLEX86_DEBUG
printf("plex86: pid %u closed device\n", p->p_pid);
#endif
return (0);
}
int
plex86_mmap(dev_t dev, vm_offset_t offset, int nprot)
{
struct proc *p = curproc;
int page;
vm_offset_t endguestoff;
vm_t *vm;
vm = find_vm(p);
if (vm == NULL)
return (ENXIO);
#warning "kludge to mmap message buffer"
endguestoff = (vm_offset_t) (vm->pages.guest_n_megs * 1024 * 1024);
if (offset >= endguestoff && nprot == PROT_READ) {
page = (offset - endguestoff) / PAGE_SIZE;
return (vm->pages.log_buffer[page]);
}
page = offset / PAGE_SIZE;
if (page < 0 || page > vm->pages.guest_n_pages) {
log(LOG_WARNING, "plex86: mmap: offset %lx out of range\n",
(unsigned long) offset);
return -1;
}
return vm->pages.guest[page];
}
int
plex86_ioctl(dev_t dev, u_long cmd, caddr_t data, int flags,
struct proc * p)
{
int error;
vm_t *vm;
vm = find_vm(p);
if (vm == NULL)
return EINVAL;
switch (cmd) {
case PLEX86_ALLOCVPHYS:
{
unsigned arg = *((unsigned *) data);
guest_cpu_t guest_cpu;
if (vm->mon_state != MON_STATE_UNINITIALIZED ||
vm->pages.guest_n_megs != 0)
return EBUSY;
if (arg > PLEX86_MAX_PHY_MEGS || arg < 4 || (arg & ~0x3) != arg)
return EINVAL;
/* Allocate memory */
error = allocVmPages(vm, arg);
if (error != 0) {
log(LOG_WARNING, "plex86: allocVmPages failed (%d)\n",
error);
return ENOMEM;
}
if (init_guest_phy_mem(vm) != 0) {
log(LOG_ERR, "plex86: init_guest_phy_mem failed\n");
unallocVmPages(vm);
return EFAULT;
}
getCpuResetValues(&guest_cpu);
log(LOG_WARNING, "plex86: cpu.cr0 = 0x%x\n", guest_cpu.cr0);
if (!init_monitor(vm, 0, 0, &guest_cpu) ||
!setGuestCPU(vm, 0, &guest_cpu) ||
!mapMonitor(vm, guest_cpu.eflags, 0)) {
log(LOG_ERR, "plex86: init_monitor failed\n");
unallocVmPages(vm);
return EFAULT;
}
break;
}
case PLEX86_TEARDOWN:
unallocVmPages(vm);
break;
case PLEX86_ALLOCINT:
return EINVAL;
case PLEX86_RELEASEINT:
return EINVAL;
case PLEX86_PRESCANDEPTH:
{
unsigned long arg = *(unsigned long *) data;
if ((arg < PrescanDepthMin) || (arg > PrescanDepthMax)) {
log(LOG_WARNING, "plex86: Requested prescan depth %lu"
" out of range [%u..%u]\n", arg, PrescanDepthMin,
PrescanDepthMax);
return EINVAL;
}
vm->prescanDepth = (unsigned) arg;
break;
}
case PLEX86_SETINTR:
ioctlSetIntr(vm, *(unsigned long *) data);
break;
case PLEX86_SET_A20:
{
unsigned long arg = *(unsigned long *) data;
if (!ioctlSetA20E(vm, arg))
return EINVAL;
break;
}
case PLEX86_MESSAGEQ:
{
vm_messages_t msg;
if (vm->mon_state != MON_STATE_RUNNABLE)
return EINVAL;
error = copyin(*(void **) data, &msg.header, sizeof msg.header);
if (error != 0)
return error;
if ((msg.header.msg_len + sizeof(msg.header)) > sizeof(msg))
return EINVAL;
if (msg.header.msg_len != 0) {
error = copyin(&((vm_messages_t *) * (void **) data)->msg,
&msg.msg, msg.header.msg_len);
if (error != 0)
return error;
}
if (ioctlMessageQ(vm, &msg)) {
log(LOG_WARNING, "plex86: ioctlMessageQ failed\n");
return EINVAL;
}
error = copyout(&msg, *(void **) data,
sizeof(msg.header) + msg.header.msg_len);
return error;
}
case PLEX86_RESET:
break;
case PLEX86_PHYMEM_MOD:
break;
case PLEX86_FORCE_INT:
if (vm->mon_state != MON_STATE_RUNNABLE)
return -EINVAL;
vm->dbg_force_int = 0x100 | (unsigned) data;
break;
case PLEX86_PRESCANRING3:
{
unsigned long arg = *(unsigned long *) data;
if (arg > PrescanRing3On) {
log(LOG_WARNING,
"plex86: Requested PrescanRing3 val(%lu) OOB\n",
arg);
return EINVAL;
}
vm->prescanRing3 = arg;
break;
}
default:
log(LOG_WARNING, "plex86: unknown ioctl %lx\n", cmd);
return EINVAL;
}
return 0;
}
static void
register_vm(vm_t * vm, struct proc * p)
{
struct plex86_hashhead *php;
struct plex86_vmentry *vhp;
php = &plex86_hashtbl[PLEX86_VMHASH(p)];
#if DIAGNOSTIC
for (vhp = php->lh_first; vhp != NULL; vhp = vhp->vm_entry.le_next) {
if (vhp->vm_pid == p->p_pid)
panic("plex86: vm already registered, pid %u\n",
p->p_pid);
}
#endif
vhp = malloc(sizeof(struct plex86_vmentry), M_PLEX86, M_WAITOK);
vhp->vm_pid = p->p_pid;
vhp->vm_vm = vm;
LIST_INSERT_HEAD(php, vhp, vm_entry);
}
static void
unregister_vm(vm_t * vm, struct proc * p)
{
struct plex86_hashhead *php;
struct plex86_vmentry *vhp;
php = &plex86_hashtbl[PLEX86_VMHASH(p)];
for (vhp = php->lh_first; vhp != NULL; vhp = vhp->vm_entry.le_next) {
if (vhp->vm_pid == p->p_pid) {
LIST_REMOVE(vhp, vm_entry);
free(vhp->vm_vm, M_PLEX86);
free(vhp, M_PLEX86);
break;
}
}
}
static void
unregister_all(struct proc * p)
{
int i;
struct plex86_hashhead *php;
struct plex86_vmentry *vhp;
php = &plex86_hashtbl[PLEX86_VMHASH(p)];
if (php == NULL)
return;
for (vhp = php->lh_first; vhp != NULL;
vhp = vhp->vm_entry.le_next) {
#ifdef FREEBSD_PLEX86_DEBUG
printf("plex86: unregister vm %p, pid %u\n",
vhp->vm_vm, vhp->vm_pid);
#endif
LIST_REMOVE(vhp, vm_entry);
if (vhp->vm_vm != NULL)
free(vhp->vm_vm, M_PLEX86);
if (vhp != NULL)
free(vhp, M_PLEX86);
}
}
static vm_t *
find_vm(struct proc * p)
{
struct plex86_hashhead *php;
struct plex86_vmentry *vhp;
php = &plex86_hashtbl[PLEX86_VMHASH(p)];
for (vhp = php->lh_first; vhp != NULL; vhp = vhp->vm_entry.le_next) {
if (vhp->vm_pid == p->p_pid)
return vhp->vm_vm;
}
return NULL;
}
static unsigned
retrieve_phy_pages(Bit32u * page, int max_pages, void *addr_v, unsigned size,
int aligned)
{
Bit32u start_addr;
unsigned n_pages, i;
if (!aligned)
start_addr = (Bit32u) addr_v & ~(PAGE_SIZE - 1);
else {
start_addr = (Bit32u) addr_v;
if (start_addr & (PAGE_SIZE - 1)) {
log(LOG_WARNING, "plex86: retrieve_phy_pages: address "
"%p not aligned\n", addr_v);
return 0;
}
}
n_pages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
if (n_pages > max_pages) {
log(LOG_WARNING, "plex86: retrieve_phy_pages: page list "
"too small\n");
return (0);
}
for (i = 0; i < n_pages; i++) {
page[i] = kvtop((vm_offset_t) start_addr) / PAGE_SIZE;
start_addr += PAGE_SIZE;
}
return n_pages;
}
unsigned
host_idle(void)
{
#if defined(want_resched)
if (want_resched) {
#endif
yield(curproc, NULL); /* XXX */
need_resched(); /* XXX */
#if defined(want_resched)
}
#endif
printf("resched done\n");
return (CURSIG(curproc) == 0);
}
void *
host_alloc(unsigned long size)
{
/*
* XXX - it wants this page-aligned apparently.
*/
if (size <= (PAGE_SIZE / 2))
size = PAGE_SIZE;
return (malloc(size, M_PLEX86, M_WAITOK));
}
void
host_free(void *ptr)
{
free(ptr, M_PLEX86);
}
unsigned
host_map(Bit32u * page, int max_pages, void *ptr, unsigned size)
{
return retrieve_phy_pages(page, max_pages, ptr, size, 1);
}
void *
host_alloc_page(void)
{
return malloc(PAGE_SIZE, M_PLEX86, M_WAITOK);
}
void
host_free_page(void *ptr)
{
return free(ptr, M_PLEX86);
}
Bit32u
host_map_page(void *ptr)
{
Bit32u u;
if (ptr == NULL)
return 0;
u = kvtop(ptr) / PAGE_SIZE;
#if FREEBSD_PLEX86_DEBUG
printf("host_map_page(%p) -> %x\n", ptr, u);
#endif
return u;
}
void
hostprint(char *fmt,...)
{
va_list args;
int ret;
unsigned char buffer[256];
va_start(args, fmt);
ret = vsnprintf(buffer, 256, fmt, args);
if (ret == -1)
log(LOG_WARNING,
"plex86: hostprint: vsnprintf returns error.\n");
else
log(LOG_WARNING, "plex86: %s\n", buffer);
}
static int
plex86_modevent(module_t mod, int type, void *data)
{
linker_file_t lf;
int error = 0;
switch (type) {
case MOD_LOAD:
plex86_hashtbl = NULL;
lf = linker_find_file_by_name("plex86");
if (lf == NULL) {
printf("plex86: can't find linker_file 'plex86'\n");
return (ENXIO);
}
monitor_pages.startOffset = lf->address;
monitor_pages.startOffsetPageAligned =
monitor_pages.startOffset & 0xfffff000;
if ((monitor_pages.n_pages = retrieve_phy_pages(monitor_pages.page,
PLEX86_MAX_MONITOR_PAGES,
lf->address,
lf->size,
0)) == 0) {
log(LOG_WARNING, "plex86: could not store physical "
"addresses for monitor pages\n");
return (ENXIO);
}
plex86_hashtbl = hashinit(PLEX86_VMHASHSIZE,
M_PLEX86, &plex86_hashmask);
if (!hostModuleInit()) {
log(LOG_WARNING, "hostModuleInit error\n");
error = EINVAL;
}
plex86_dev = make_dev(&plex86_cdevsw, 0 /* minor */ , UID_ROOT,
GID_WHEEL, 0600, "plex86");
printf("plex86: Module loaded.\n");
return (0);
break;
case MOD_UNLOAD:
if (plex86sc.sc_open != 0)
return (EBUSY);
destroy_dev(plex86_dev);
if (plex86_hashtbl != NULL) {
free(plex86_hashtbl, M_PLEX86);
}
printf("plex86: Module unloaded.\n");
break;
default:
error = ENXIO;
break;
}
return (error);
}
MODULE_VERSION(plex86, 1);
DEV_MODULE(plex86, plex86_modevent, 0);