KVM: s390: streamline memslot handling

This patch relocates the variables kvm-s390 uses to track guest mem addr/size.
As discussed dropping the variables at struct kvm_arch level allows to use the
common vcpu->request based mechanism to reload guest memory if e.g. changes
via set_memory_region.

The kick mechanism introduced in this series is used to ensure running vcpus
leave guest state to catch the update.

Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Christian Ehrhardt 2009-05-25 13:40:51 +02:00 committed by Avi Kivity
parent b1d16c495d
commit 628eb9b8a8
6 changed files with 62 additions and 54 deletions

View file

@ -1,7 +1,7 @@
/*
* asm-s390/kvm_host.h - definition for kernel virtual machines on s390
*
* Copyright IBM Corp. 2008
* Copyright IBM Corp. 2008,2009
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License (version 2 only)
@ -228,8 +228,6 @@ struct kvm_vm_stat {
};
struct kvm_arch{
unsigned long guest_origin;
unsigned long guest_memsize;
struct sca_block *sca;
debug_info_t *dbf;
struct kvm_s390_float_interrupt float_int;

View file

@ -1,7 +1,7 @@
/*
* gaccess.h - access guest memory
*
* Copyright IBM Corp. 2008
* Copyright IBM Corp. 2008,2009
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License (version 2 only)
@ -16,13 +16,14 @@
#include <linux/compiler.h>
#include <linux/kvm_host.h>
#include <asm/uaccess.h>
#include "kvm-s390.h"
static inline void __user *__guestaddr_to_user(struct kvm_vcpu *vcpu,
unsigned long guestaddr)
{
unsigned long prefix = vcpu->arch.sie_block->prefix;
unsigned long origin = vcpu->kvm->arch.guest_origin;
unsigned long memsize = vcpu->kvm->arch.guest_memsize;
unsigned long origin = vcpu->arch.sie_block->gmsor;
unsigned long memsize = kvm_s390_vcpu_get_memsize(vcpu);
if (guestaddr < 2 * PAGE_SIZE)
guestaddr += prefix;
@ -158,8 +159,8 @@ static inline int copy_to_guest(struct kvm_vcpu *vcpu, unsigned long guestdest,
const void *from, unsigned long n)
{
unsigned long prefix = vcpu->arch.sie_block->prefix;
unsigned long origin = vcpu->kvm->arch.guest_origin;
unsigned long memsize = vcpu->kvm->arch.guest_memsize;
unsigned long origin = vcpu->arch.sie_block->gmsor;
unsigned long memsize = kvm_s390_vcpu_get_memsize(vcpu);
if ((guestdest < 2 * PAGE_SIZE) && (guestdest + n > 2 * PAGE_SIZE))
goto slowpath;
@ -209,8 +210,8 @@ static inline int copy_from_guest(struct kvm_vcpu *vcpu, void *to,
unsigned long guestsrc, unsigned long n)
{
unsigned long prefix = vcpu->arch.sie_block->prefix;
unsigned long origin = vcpu->kvm->arch.guest_origin;
unsigned long memsize = vcpu->kvm->arch.guest_memsize;
unsigned long origin = vcpu->arch.sie_block->gmsor;
unsigned long memsize = kvm_s390_vcpu_get_memsize(vcpu);
if ((guestsrc < 2 * PAGE_SIZE) && (guestsrc + n > 2 * PAGE_SIZE))
goto slowpath;
@ -244,8 +245,8 @@ static inline int copy_to_guest_absolute(struct kvm_vcpu *vcpu,
unsigned long guestdest,
const void *from, unsigned long n)
{
unsigned long origin = vcpu->kvm->arch.guest_origin;
unsigned long memsize = vcpu->kvm->arch.guest_memsize;
unsigned long origin = vcpu->arch.sie_block->gmsor;
unsigned long memsize = kvm_s390_vcpu_get_memsize(vcpu);
if (guestdest + n > memsize)
return -EFAULT;
@ -262,8 +263,8 @@ static inline int copy_from_guest_absolute(struct kvm_vcpu *vcpu, void *to,
unsigned long guestsrc,
unsigned long n)
{
unsigned long origin = vcpu->kvm->arch.guest_origin;
unsigned long memsize = vcpu->kvm->arch.guest_memsize;
unsigned long origin = vcpu->arch.sie_block->gmsor;
unsigned long memsize = kvm_s390_vcpu_get_memsize(vcpu);
if (guestsrc + n > memsize)
return -EFAULT;

View file

@ -1,7 +1,7 @@
/*
* intercept.c - in-kernel handling for sie intercepts
*
* Copyright IBM Corp. 2008
* Copyright IBM Corp. 2008,2009
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License (version 2 only)
@ -164,9 +164,9 @@ static int handle_validity(struct kvm_vcpu *vcpu)
vcpu->stat.exit_validity++;
if ((viwhy == 0x37) && (vcpu->arch.sie_block->prefix
<= vcpu->kvm->arch.guest_memsize - 2*PAGE_SIZE)){
<= kvm_s390_vcpu_get_memsize(vcpu) - 2*PAGE_SIZE)) {
rc = fault_in_pages_writeable((char __user *)
vcpu->kvm->arch.guest_origin +
vcpu->arch.sie_block->gmsor +
vcpu->arch.sie_block->prefix,
2*PAGE_SIZE);
if (rc)

View file

@ -1,7 +1,7 @@
/*
* s390host.c -- hosting zSeries kernel virtual machines
*
* Copyright IBM Corp. 2008
* Copyright IBM Corp. 2008,2009
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License (version 2 only)
@ -10,6 +10,7 @@
* Author(s): Carsten Otte <cotte@de.ibm.com>
* Christian Borntraeger <borntraeger@de.ibm.com>
* Heiko Carstens <heiko.carstens@de.ibm.com>
* Christian Ehrhardt <ehrhardt@de.ibm.com>
*/
#include <linux/compiler.h>
@ -278,16 +279,10 @@ static void kvm_s390_vcpu_initial_reset(struct kvm_vcpu *vcpu)
vcpu->arch.sie_block->gbea = 1;
}
/* The current code can have up to 256 pages for virtio */
#define VIRTIODESCSPACE (256ul * 4096ul)
int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
{
atomic_set(&vcpu->arch.sie_block->cpuflags, CPUSTAT_ZARCH);
vcpu->arch.sie_block->gmslm = vcpu->kvm->arch.guest_memsize +
vcpu->kvm->arch.guest_origin +
VIRTIODESCSPACE - 1ul;
vcpu->arch.sie_block->gmsor = vcpu->kvm->arch.guest_origin;
set_bit(KVM_REQ_MMU_RELOAD, &vcpu->requests);
vcpu->arch.sie_block->ecb = 2;
vcpu->arch.sie_block->eca = 0xC1002001U;
vcpu->arch.sie_block->fac = (int) (long) facilities;
@ -491,9 +486,14 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
vcpu_load(vcpu);
rerun_vcpu:
if (vcpu->requests)
if (test_and_clear_bit(KVM_REQ_MMU_RELOAD, &vcpu->requests))
kvm_s390_vcpu_set_mem(vcpu);
/* verify, that memory has been registered */
if (!vcpu->kvm->arch.guest_memsize) {
if (!vcpu->arch.sie_block->gmslm) {
vcpu_put(vcpu);
VCPU_EVENT(vcpu, 3, "%s", "no memory registered to run vcpu");
return -EINVAL;
}
@ -691,7 +691,7 @@ int kvm_arch_set_memory_region(struct kvm *kvm,
vmas. It is okay to mmap() and munmap() stuff in this slot after
doing this call at any time */
if (mem->slot || kvm->arch.guest_memsize)
if (mem->slot)
return -EINVAL;
if (mem->guest_phys_addr)
@ -706,36 +706,18 @@ int kvm_arch_set_memory_region(struct kvm *kvm,
if (!user_alloc)
return -EINVAL;
/* lock all vcpus */
for (i = 0; i < KVM_MAX_VCPUS; ++i) {
if (!kvm->vcpus[i])
continue;
if (!mutex_trylock(&kvm->vcpus[i]->mutex))
goto fail_out;
}
kvm->arch.guest_origin = mem->userspace_addr;
kvm->arch.guest_memsize = mem->memory_size;
/* update sie control blocks, and unlock all vcpus */
/* request update of sie control block for all available vcpus */
for (i = 0; i < KVM_MAX_VCPUS; ++i) {
if (kvm->vcpus[i]) {
kvm->vcpus[i]->arch.sie_block->gmsor =
kvm->arch.guest_origin;
kvm->vcpus[i]->arch.sie_block->gmslm =
kvm->arch.guest_memsize +
kvm->arch.guest_origin +
VIRTIODESCSPACE - 1ul;
mutex_unlock(&kvm->vcpus[i]->mutex);
if (test_and_set_bit(KVM_REQ_MMU_RELOAD,
&kvm->vcpus[i]->requests))
continue;
kvm_s390_inject_sigp_stop(kvm->vcpus[i],
ACTION_RELOADVCPU_ON_STOP);
}
}
return 0;
fail_out:
for (; i >= 0; i--)
mutex_unlock(&kvm->vcpus[i]->mutex);
return -EINVAL;
}
void kvm_arch_flush_shadow(struct kvm *kvm)

View file

@ -1,7 +1,7 @@
/*
* kvm_s390.h - definition for kvm on s390
*
* Copyright IBM Corp. 2008
* Copyright IBM Corp. 2008,2009
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License (version 2 only)
@ -9,6 +9,7 @@
*
* Author(s): Carsten Otte <cotte@de.ibm.com>
* Christian Borntraeger <borntraeger@de.ibm.com>
* Christian Ehrhardt <ehrhardt@de.ibm.com>
*/
#ifndef ARCH_S390_KVM_S390_H
@ -18,6 +19,9 @@
#include <linux/kvm.h>
#include <linux/kvm_host.h>
/* The current code can have up to 256 pages for virtio */
#define VIRTIODESCSPACE (256ul * 4096ul)
typedef int (*intercept_handler_t)(struct kvm_vcpu *vcpu);
/* negativ values are error codes, positive values for internal conditions */
@ -54,6 +58,29 @@ int kvm_s390_inject_vcpu(struct kvm_vcpu *vcpu,
int kvm_s390_inject_program_int(struct kvm_vcpu *vcpu, u16 code);
int kvm_s390_inject_sigp_stop(struct kvm_vcpu *vcpu, int action);
static inline int kvm_s390_vcpu_get_memsize(struct kvm_vcpu *vcpu)
{
return vcpu->arch.sie_block->gmslm
- vcpu->arch.sie_block->gmsor
- VIRTIODESCSPACE + 1ul;
}
static inline void kvm_s390_vcpu_set_mem(struct kvm_vcpu *vcpu)
{
struct kvm_memory_slot *mem;
down_read(&vcpu->kvm->slots_lock);
mem = &vcpu->kvm->memslots[0];
vcpu->arch.sie_block->gmsor = mem->userspace_addr;
vcpu->arch.sie_block->gmslm =
mem->userspace_addr +
(mem->npages << PAGE_SHIFT) +
VIRTIODESCSPACE - 1ul;
up_read(&vcpu->kvm->slots_lock);
}
/* implemented in priv.c */
int kvm_s390_handle_b2(struct kvm_vcpu *vcpu);

View file

@ -189,9 +189,9 @@ static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
/* make sure that the new value is valid memory */
address = address & 0x7fffe000u;
if ((copy_from_guest(vcpu, &tmp,
(u64) (address + vcpu->kvm->arch.guest_origin) , 1)) ||
(u64) (address + vcpu->arch.sie_block->gmsor) , 1)) ||
(copy_from_guest(vcpu, &tmp, (u64) (address +
vcpu->kvm->arch.guest_origin + PAGE_SIZE), 1))) {
vcpu->arch.sie_block->gmsor + PAGE_SIZE), 1))) {
*reg |= SIGP_STAT_INVALID_PARAMETER;
return 1; /* invalid parameter */
}