Commit cc65c3a1 authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
Browse files

KVM: s390: Replace KVM_REQ_MMU_RELOAD usage with arch specific request 



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.

Reviewed-by: default avatarClaudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: default avatarJanosch Frank <frankja@linux.ibm.com>
Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
Message-Id: <20220225182248.3812651-6-seanjc@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 527d5cd7

arch/s390/include/asm/kvm_host.h

+2 −0
Original line number Diff line number Diff line
@@ -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

arch/s390/kvm/kvm-s390.c

+4 −4
Original line number Diff line number Diff line
@@ -3481,7 +3481,7 @@ 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);

		}

	}

}
@@ -3883,19 +3883,19 @@ 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;

arch/s390/kvm/kvm-s390.h

+1 −1
Original line number Diff line number Diff line
@@ -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)