[PATCH 5/7] KVM: s390: Replace KVM_REQ_MMU_RELOAD usage with arch specific request

Sean Christopherson
2021-12-09T06:06:16Z

Add an arch request, KVM_REQ_REFRESH_GUEST_PREFIX, to deal with guest
prefix changes instead of piggybacking KVM_REQ_MMU_RELOAD. This will
allow for the removal of the generic KVM_REQ_MMU_RELOAD, which isn't
actually used by generic KVM.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
arch/s390/include/asm/kvm_host.h | 2 ++
arch/s390/kvm/kvm-s390.c | 8 ++++----
arch/s390/kvm/kvm-s390.h | 2 +-
3 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index a22c9266ea05..766028d54a3e 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -45,6 +45,8 @@
#define KVM_REQ_START_MIGRATION KVM_ARCH_REQ(3)
#define KVM_REQ_STOP_MIGRATION KVM_ARCH_REQ(4)
#define KVM_REQ_VSIE_RESTART KVM_ARCH_REQ(5)
+#define KVM_REQ_REFRESH_GUEST_PREFIX \
+ KVM_ARCH_REQ_FLAGS(6, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP)

#define SIGP_CTRL_C 0x80
#define SIGP_CTRL_SCN_MASK 0x3f
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index dd099d352753..e161df69520c 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -3394,7 +3394,7 @@ static void kvm_gmap_notifier(struct gmap *gmap, unsigned long start,
if (prefix <= end && start <= prefix + 2*PAGE_SIZE - 1) {
VCPU_EVENT(vcpu, 2, "gmap notifier for %lx-%lx",
start, end);
- kvm_s390_sync_request(KVM_REQ_MMU_RELOAD, vcpu);
+ kvm_s390_sync_request(KVM_REQ_REFRESH_GUEST_PREFIX, vcpu);
}
}
}
@@ -3796,19 +3796,19 @@ static int kvm_s390_handle_requests(struct kvm_vcpu *vcpu)
if (!kvm_request_pending(vcpu))
return 0;
/*
- * We use MMU_RELOAD just to re-arm the ipte notifier for the
+ * If the guest prefix changed, re-arm the ipte notifier for the
* guest prefix page. gmap_mprotect_notify will wait on the ptl lock.
* This ensures that the ipte instruction for this request has
* already finished. We might race against a second unmapper that
* wants to set the blocking bit. Lets just retry the request loop.
*/
- if (kvm_check_request(KVM_REQ_MMU_RELOAD, vcpu)) {
+ if (kvm_check_request(KVM_REQ_REFRESH_GUEST_PREFIX, vcpu)) {
int rc;
rc = gmap_mprotect_notify(vcpu->arch.gmap,
kvm_s390_get_prefix(vcpu),
PAGE_SIZE * 2, PROT_WRITE);
if (rc) {
- kvm_make_request(KVM_REQ_MMU_RELOAD, vcpu);
+ kvm_make_request(KVM_REQ_REFRESH_GUEST_PREFIX, vcpu);
return rc;
}
goto retry;
diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index 60f0effcce99..219f92ffd556 100644
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -105,7 +105,7 @@ static inline void kvm_s390_set_prefix(struct kvm_vcpu *vcpu, u32 prefix)
prefix);
vcpu->arch.sie_block->prefix = prefix >> GUEST_PREFIX_SHIFT;
kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);
- kvm_make_request(KVM_REQ_MMU_RELOAD, vcpu);
+ kvm_make_request(KVM_REQ_REFRESH_GUEST_PREFIX, vcpu);
}

static inline u64 kvm_s390_get_base_disp_s(struct kvm_vcpu *vcpu, u8 *ar)
--
2.34.1.400.ga245620fadb-goog