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>
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 5c1c302..098bfa6 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -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 @@
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 @@
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 @@
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 @@
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)