freebsd-skq/usr.sbin/bhyve/kernemu_dev.c
cem 911aeff04c vmm(4), bhyve(8): Expose kernel-emulated special devices to userspace
Expose the special kernel LAPIC, IOAPIC, and HPET devices to userspace
for use in, e.g., fallback instruction emulation (when userspace has a
newer instruction decode/emulation layer than the kernel vmm(4)).

Plumb the ioctl through libvmmapi and register the memory ranges in
bhyve(8).

Reviewed by:	grehan
Differential Revision:	https://reviews.freebsd.org/D24525
2020-05-15 15:54:22 +00:00

99 lines
3.0 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright 2020 Conrad Meyer <cem@FreeBSD.org>. 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/errno.h>
#include <sys/tree.h>
#include <amd64/include/vmm.h>
#include <x86/include/apicreg.h>
struct vm;
struct vm_hpet_cap;
#include <vmm/io/vioapic.h>
#include <vmm/io/vhpet.h>
#include <err.h>
#include <errno.h>
#include <vmmapi.h>
#include "kernemu_dev.h"
#include "mem.h"
static int
apic_handler(struct vmctx *ctx, int vcpu, int dir, uint64_t addr, int size,
uint64_t *val, void *arg1 __unused, long arg2 __unused)
{
if (vm_readwrite_kernemu_device(ctx, vcpu, addr, (dir == MEM_F_WRITE),
size, val) != 0)
return (errno);
return (0);
}
static struct mem_range lapic_mmio = {
.name = "kern-lapic-mmio",
.base = DEFAULT_APIC_BASE,
.size = PAGE_SIZE,
.flags = MEM_F_RW | MEM_F_IMMUTABLE,
.handler = apic_handler,
};
static struct mem_range ioapic_mmio = {
.name = "kern-ioapic-mmio",
.base = VIOAPIC_BASE,
.size = VIOAPIC_SIZE,
.flags = MEM_F_RW | MEM_F_IMMUTABLE,
.handler = apic_handler,
};
static struct mem_range hpet_mmio = {
.name = "kern-hpet-mmio",
.base = VHPET_BASE,
.size = VHPET_SIZE,
.flags = MEM_F_RW | MEM_F_IMMUTABLE,
.handler = apic_handler,
};
void
kernemu_dev_init(void)
{
int rc;
rc = register_mem(&lapic_mmio);
if (rc != 0)
errc(4, rc, "register_mem: LAPIC (0x%08x)",
(unsigned)lapic_mmio.base);
rc = register_mem(&ioapic_mmio);
if (rc != 0)
errc(4, rc, "register_mem: IOAPIC (0x%08x)",
(unsigned)ioapic_mmio.base);
rc = register_mem(&hpet_mmio);
if (rc != 0)
errc(4, rc, "register_mem: HPET (0x%08x)",
(unsigned)hpet_mmio.base);
}