NetBSD/sys/arch/xen/x86/xen_ipi.c

355 lines
8.1 KiB
C

/* $NetBSD: xen_ipi.c,v 1.39 2020/05/07 19:48:58 bouyer Exp $ */
/*-
* Copyright (c) 2011, 2019 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Cherry G. Mathew <cherry@zyx.in>
*
* 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.
*/
#include <sys/cdefs.h> /* RCS ID macro */
/*
* Based on: x86/ipi.c
*/
__KERNEL_RCSID(0, "$NetBSD: xen_ipi.c,v 1.39 2020/05/07 19:48:58 bouyer Exp $");
#include "opt_ddb.h"
#include <sys/types.h>
#include <sys/atomic.h>
#include <sys/cpu.h>
#include <sys/mutex.h>
#include <sys/device.h>
#include <sys/xcall.h>
#include <sys/ipi.h>
#include <sys/errno.h>
#include <sys/systm.h>
#include <x86/fpu.h>
#include <machine/frame.h>
#include <machine/segments.h>
#include <xen/evtchn.h>
#include <xen/intr.h>
#include <xen/intrdefs.h>
#include <xen/hypervisor.h>
#include <xen/include/public/vcpu.h>
#ifdef DDB
extern void ddb_ipi(struct trapframe);
static void xen_ipi_ddb(struct cpu_info *, struct intrframe *);
#endif
static void xen_ipi_halt(struct cpu_info *, struct intrframe *);
static void xen_ipi_synch_fpu(struct cpu_info *, struct intrframe *);
static void xen_ipi_xcall(struct cpu_info *, struct intrframe *);
static void xen_ipi_hvcb(struct cpu_info *, struct intrframe *);
static void xen_ipi_generic(struct cpu_info *, struct intrframe *);
static void xen_ipi_ast(struct cpu_info *, struct intrframe *);
static void xen_ipi_kpreempt(struct cpu_info *ci, struct intrframe *);
static void (*xen_ipifunc[XEN_NIPIS])(struct cpu_info *, struct intrframe *) =
{ /* In order of priority (see: xen/include/intrdefs.h */
xen_ipi_halt,
xen_ipi_synch_fpu,
#ifdef DDB
xen_ipi_ddb,
#else
NULL,
#endif
xen_ipi_xcall,
xen_ipi_hvcb,
xen_ipi_generic,
xen_ipi_ast,
xen_ipi_kpreempt
};
static int
xen_ipi_handler(void *arg)
{
uint32_t pending;
int bit;
struct cpu_info *ci;
struct intrframe *regs;
ci = curcpu();
regs = arg;
KASSERT(ci == arg);
pending = atomic_swap_32(&ci->ci_ipis, 0);
KDASSERT((pending >> XEN_NIPIS) == 0);
while ((bit = ffs(pending)) != 0) {
bit--;
pending &= ~(1 << bit);
ci->ci_ipi_events[bit].ev_count++;
if (xen_ipifunc[bit] != NULL) {
(*xen_ipifunc[bit])(ci, regs);
} else {
panic("xen_ipifunc[%d] unsupported!\n", bit);
/* NOTREACHED */
}
}
return 0;
}
/* Must be called once for every cpu that expects to send/recv ipis */
void
xen_ipi_init(void)
{
cpuid_t vcpu;
evtchn_port_t evtchn;
struct cpu_info *ci;
char intr_xname[INTRDEVNAMEBUF];
ci = curcpu();
vcpu = ci->ci_vcpuid;
KASSERT(vcpu < XEN_LEGACY_MAX_VCPUS);
evtchn = bind_vcpu_to_evtch(vcpu);
ci->ci_ipi_evtchn = evtchn;
KASSERT(evtchn != -1 && evtchn < NR_EVENT_CHANNELS);
snprintf(intr_xname, sizeof(intr_xname), "%s ipi",
device_xname(ci->ci_dev));
if (event_set_handler(evtchn, xen_ipi_handler, ci, IPL_HIGH, NULL,
intr_xname, true, ci) == NULL) {
panic("%s: unable to register ipi handler\n", __func__);
/* NOTREACHED */
}
hypervisor_unmask_event(evtchn);
}
#ifdef DIAGNOSTIC
static inline bool /* helper */
valid_ipimask(uint32_t ipimask)
{
uint32_t masks = XEN_IPI_GENERIC | XEN_IPI_HVCB | XEN_IPI_XCALL |
XEN_IPI_DDB | XEN_IPI_SYNCH_FPU |
XEN_IPI_HALT | XEN_IPI_AST | XEN_IPI_KPREEMPT;
if (ipimask & ~masks) {
return false;
} else {
return true;
}
}
#endif
int
xen_send_ipi(struct cpu_info *ci, uint32_t ipimask)
{
evtchn_port_t evtchn;
KASSERT(ci != NULL && ci != curcpu());
if ((ci->ci_flags & CPUF_RUNNING) == 0) {
return ENOENT;
}
evtchn = ci->ci_ipi_evtchn;
KASSERTMSG(valid_ipimask(ipimask) == true,
"xen_send_ipi() called with invalid ipimask\n");
atomic_or_32(&ci->ci_ipis, ipimask);
hypervisor_notify_via_evtchn(evtchn);
return 0;
}
void
xen_broadcast_ipi(uint32_t ipimask)
{
struct cpu_info *ci, *self = curcpu();
CPU_INFO_ITERATOR cii;
KASSERTMSG(valid_ipimask(ipimask) == true,
"xen_broadcast_ipi() called with invalid ipimask\n");
/*
* XXX-cherry: there's an implicit broadcast sending order
* which I dislike. Randomise this ? :-)
*/
for (CPU_INFO_FOREACH(cii, ci)) {
if (ci == NULL)
continue;
if (ci == self)
continue;
if (ci->ci_data.cpu_idlelwp == NULL)
continue;
if ((ci->ci_flags & CPUF_PRESENT) == 0)
continue;
if (ci->ci_flags & (CPUF_RUNNING)) {
if (0 != xen_send_ipi(ci, ipimask)) {
panic("xen_ipi of %x from %s to %s failed\n",
ipimask, cpu_name(curcpu()),
cpu_name(ci));
}
}
}
}
/* MD wrapper for the xcall(9) callback. */
static void
xen_ipi_halt(struct cpu_info *ci, struct intrframe *intrf)
{
KASSERT(ci == curcpu());
KASSERT(ci != NULL);
if (HYPERVISOR_vcpu_op(VCPUOP_down, ci->ci_vcpuid, NULL)) {
panic("%s shutdown failed.\n", device_xname(ci->ci_dev));
}
}
static void
xen_ipi_synch_fpu(struct cpu_info *ci, struct intrframe *intrf)
{
KASSERT(ci != NULL);
KASSERT(intrf != NULL);
panic("%s: impossible", __func__);
}
#ifdef DDB
static void
xen_ipi_ddb(struct cpu_info *ci, struct intrframe *intrf)
{
KASSERT(ci != NULL);
KASSERT(intrf != NULL);
#ifdef __x86_64__
ddb_ipi(intrf->if_tf);
#else
struct trapframe tf;
tf.tf_gs = intrf->if_gs;
tf.tf_fs = intrf->if_fs;
tf.tf_es = intrf->if_es;
tf.tf_ds = intrf->if_ds;
tf.tf_edi = intrf->if_edi;
tf.tf_esi = intrf->if_esi;
tf.tf_ebp = intrf->if_ebp;
tf.tf_ebx = intrf->if_ebx;
tf.tf_ecx = intrf->if_ecx;
tf.tf_eax = intrf->if_eax;
tf.tf_trapno = intrf->__if_trapno;
tf.tf_err = intrf->__if_err;
tf.tf_eip = intrf->if_eip;
tf.tf_cs = intrf->if_cs;
tf.tf_eflags = intrf->if_eflags;
tf.tf_esp = intrf->if_esp;
tf.tf_ss = intrf->if_ss;
ddb_ipi(tf);
#endif
}
#endif /* DDB */
static void
xen_ipi_xcall(struct cpu_info *ci, struct intrframe *intrf)
{
KASSERT(ci != NULL);
KASSERT(intrf != NULL);
xc_ipi_handler();
}
static void
xen_ipi_ast(struct cpu_info *ci, struct intrframe *intrf)
{
KASSERT(ci != NULL);
KASSERT(intrf != NULL);
aston(ci->ci_onproc);
}
static void
xen_ipi_generic(struct cpu_info *ci, struct intrframe *intrf)
{
KASSERT(ci != NULL);
KASSERT(intrf != NULL);
ipi_cpu_handler();
}
static void
xen_ipi_hvcb(struct cpu_info *ci, struct intrframe *intrf)
{
KASSERT(ci != NULL);
KASSERT(intrf != NULL);
KASSERT(ci == curcpu());
KASSERT(!ci->ci_vcpu->evtchn_upcall_mask);
hypervisor_force_callback();
}
static void
xen_ipi_kpreempt(struct cpu_info *ci, struct intrframe * intrf)
{
softint_trigger(1 << SIR_PREEMPT);
}
#ifdef XENPV
void
xc_send_ipi(struct cpu_info *ci)
{
KASSERT(kpreempt_disabled());
KASSERT(curcpu() != ci);
if (ci) {
if (0 != xen_send_ipi(ci, XEN_IPI_XCALL)) {
panic("xen_send_ipi(XEN_IPI_XCALL) failed\n");
}
} else {
xen_broadcast_ipi(XEN_IPI_XCALL);
}
}
void
cpu_ipi(struct cpu_info *ci)
{
KASSERT(kpreempt_disabled());
KASSERT(curcpu() != ci);
if (ci) {
if (0 != xen_send_ipi(ci, XEN_IPI_GENERIC)) {
panic("xen_send_ipi(XEN_IPI_GENERIC) failed\n");
}
} else {
xen_broadcast_ipi(XEN_IPI_GENERIC);
}
}
#endif /* XENPV */