1 files changed, 207 insertions, 27 deletions

diff --git a/sys/amd64/vmm/vmm.c b/sys/amd64/vmm/vmm.c
index f471218b..2c86068 100644
--- a/sys/amd64/vmm/vmm.c
+++ b/sys/amd64/vmm/vmm.c
@@ -124,19 +124,25 @@ struct vm {
 	 * An active vcpu is one that has been started implicitly (BSP) or
 	 * explicitly (AP) by sending it a startup ipi.
 	 */
-	cpuset_t	active_cpus;
+	volatile cpuset_t active_cpus;
+
+	struct mtx	rendezvous_mtx;
+	cpuset_t	rendezvous_req_cpus;
+	cpuset_t	rendezvous_done_cpus;
+	void		*rendezvous_arg;
+	vm_rendezvous_func_t rendezvous_func;
 };
 
 static int vmm_initialized;
 
 static struct vmm_ops *ops;
-#define	VMM_INIT()	(ops != NULL ? (*ops->init)() : 0)
+#define	VMM_INIT(num)	(ops != NULL ? (*ops->init)(num) : 0)
 #define	VMM_CLEANUP()	(ops != NULL ? (*ops->cleanup)() : 0)
 #define	VMM_RESUME()	(ops != NULL ? (*ops->resume)() : 0)
 
 #define	VMINIT(vm, pmap) (ops != NULL ? (*ops->vminit)(vm, pmap): NULL)
-#define	VMRUN(vmi, vcpu, rip, pmap) \
-	(ops != NULL ? (*ops->vmrun)(vmi, vcpu, rip, pmap) : ENXIO)
+#define	VMRUN(vmi, vcpu, rip, pmap, rptr) \
+	(ops != NULL ? (*ops->vmrun)(vmi, vcpu, rip, pmap, rptr) : ENXIO)
 #define	VMCLEANUP(vmi)	(ops != NULL ? (*ops->vmcleanup)(vmi) : NULL)
 #define	VMSPACE_ALLOC(min, max) \
 	(ops != NULL ? (*ops->vmspace_alloc)(min, max) : NULL)
@@ -156,6 +162,10 @@ static struct vmm_ops *ops;
 	(ops != NULL ? (*ops->vmgetcap)(vmi, vcpu, num, retval) : ENXIO)
 #define	VMSETCAP(vmi, vcpu, num, val)		\
 	(ops != NULL ? (*ops->vmsetcap)(vmi, vcpu, num, val) : ENXIO)
+#define	VLAPIC_INIT(vmi, vcpu)			\
+	(ops != NULL ? (*ops->vlapic_init)(vmi, vcpu) : NULL)
+#define	VLAPIC_CLEANUP(vmi, vlapic)		\
+	(ops != NULL ? (*ops->vlapic_cleanup)(vmi, vlapic) : NULL)
 
 #define	fpu_start_emulating()	load_cr0(rcr0() | CR0_TS)
 #define	fpu_stop_emulating()	clts()
@@ -166,10 +176,20 @@ CTASSERT(VMM_MSR_NUM <= 64);	/* msr_mask can keep track of up to 64 msrs */
 /* statistics */
 static VMM_STAT(VCPU_TOTAL_RUNTIME, "vcpu total runtime");
 
+SYSCTL_NODE(_hw, OID_AUTO, vmm, CTLFLAG_RW, NULL, NULL);
+
+static int vmm_ipinum;
+SYSCTL_INT(_hw_vmm, OID_AUTO, ipinum, CTLFLAG_RD, &vmm_ipinum, 0,
+    "IPI vector used for vcpu notifications");
+
+static void vm_deactivate_cpu(struct vm *vm, int vcpuid);
+
 static void
-vcpu_cleanup(struct vcpu *vcpu)
+vcpu_cleanup(struct vm *vm, int i)
 {
-	vlapic_cleanup(vcpu->vlapic);
+	struct vcpu *vcpu = &vm->vcpu[i];
+
+	VLAPIC_CLEANUP(vm->cookie, vcpu->vlapic);
 	vmm_stat_free(vcpu->stats);	
 	fpu_save_area_free(vcpu->guestfpu);
 }
@@ -184,7 +204,7 @@ vcpu_init(struct vm *vm, uint32_t vcpu_id)
 	vcpu_lock_init(vcpu);
 	vcpu->hostcpu = NOCPU;
 	vcpu->vcpuid = vcpu_id;
-	vcpu->vlapic = vlapic_init(vm, vcpu_id);
+	vcpu->vlapic = VLAPIC_INIT(vm->cookie, vcpu_id);
 	vm_set_x2apic_state(vm, vcpu_id, X2APIC_ENABLED);
 	vcpu->guestfpu = fpu_save_area_alloc();
 	fpu_save_area_reset(vcpu->guestfpu);
@@ -216,7 +236,10 @@ vmm_init(void)
 	int error;
 
 	vmm_host_state_init();
-	vmm_ipi_init();
+
+	vmm_ipinum = vmm_ipi_alloc();
+	if (vmm_ipinum == 0)
+		vmm_ipinum = IPI_AST;
 
 	error = vmm_mem_init();
 	if (error)
@@ -232,7 +255,7 @@ vmm_init(void)
 	vmm_msr_init();
 	vmm_resume_p = vmm_resume;
 
-	return (VMM_INIT());
+	return (VMM_INIT(vmm_ipinum));
 }
 
 static int
@@ -253,7 +276,8 @@ vmm_handler(module_t mod, int what, void *arg)
 		if (error == 0) {
 			vmm_resume_p = NULL;
 			iommu_cleanup();
-			vmm_ipi_cleanup();
+			if (vmm_ipinum != IPI_AST)
+				vmm_ipi_free(vmm_ipinum);
 			error = VMM_CLEANUP();
 			/*
 			 * Something bad happened - prevent new
@@ -288,8 +312,6 @@ static moduledata_t vmm_kmod = {
 DECLARE_MODULE(vmm, vmm_kmod, SI_SUB_SMP + 1, SI_ORDER_ANY);
 MODULE_VERSION(vmm, 1);
 
-SYSCTL_NODE(_hw, OID_AUTO, vmm, CTLFLAG_RW, NULL, NULL);
-
 int
 vm_create(const char *name, struct vm **retvm)
 {
@@ -315,6 +337,8 @@ vm_create(const char *name, struct vm **retvm)
 
 	vm = malloc(sizeof(struct vm), M_VM, M_WAITOK | M_ZERO);
 	strcpy(vm->name, name);
+	vm->vmspace = vmspace;
+	mtx_init(&vm->rendezvous_mtx, "vm rendezvous lock", 0, MTX_DEF);
 	vm->cookie = VMINIT(vm, vmspace_pmap(vmspace));
 	vm->vioapic = vioapic_init(vm);
 	vm->vhpet = vhpet_init(vm);
@@ -325,7 +349,6 @@ vm_create(const char *name, struct vm **retvm)
 	}
 
 	vm_activate_cpu(vm, BSP);
-	vm->vmspace = vmspace;
 
 	*retvm = vm;
 	return (0);
@@ -360,7 +383,7 @@ vm_destroy(struct vm *vm)
 	vm->num_mem_segs = 0;
 
 	for (i = 0; i < VM_MAXCPU; i++)
-		vcpu_cleanup(&vm->vcpu[i]);
+		vcpu_cleanup(vm, i);
 
 	VMSPACE_FREE(vm->vmspace);
 
@@ -866,6 +889,63 @@ vcpu_require_state_locked(struct vcpu *vcpu, enum vcpu_state newstate)
 		panic("Error %d setting state to %d", error, newstate);
 }
 
+static void
+vm_set_rendezvous_func(struct vm *vm, vm_rendezvous_func_t func)
+{
+
+	KASSERT(mtx_owned(&vm->rendezvous_mtx), ("rendezvous_mtx not locked"));
+
+	/*
+	 * Update 'rendezvous_func' and execute a write memory barrier to
+	 * ensure that it is visible across all host cpus. This is not needed
+	 * for correctness but it does ensure that all the vcpus will notice
+	 * that the rendezvous is requested immediately.
+	 */
+	vm->rendezvous_func = func;
+	wmb();
+}
+
+#define	RENDEZVOUS_CTR0(vm, vcpuid, fmt)				\
+	do {								\
+		if (vcpuid >= 0)					\
+			VCPU_CTR0(vm, vcpuid, fmt);			\
+		else							\
+			VM_CTR0(vm, fmt);				\
+	} while (0)
+
+static void
+vm_handle_rendezvous(struct vm *vm, int vcpuid)
+{
+
+	KASSERT(vcpuid == -1 || (vcpuid >= 0 && vcpuid < VM_MAXCPU),
+	    ("vm_handle_rendezvous: invalid vcpuid %d", vcpuid));
+
+	mtx_lock(&vm->rendezvous_mtx);
+	while (vm->rendezvous_func != NULL) {
+		/* 'rendezvous_req_cpus' must be a subset of 'active_cpus' */
+		CPU_AND(&vm->rendezvous_req_cpus, &vm->active_cpus);
+
+		if (vcpuid != -1 &&
+		    CPU_ISSET(vcpuid, &vm->rendezvous_req_cpus) &&
+		    !CPU_ISSET(vcpuid, &vm->rendezvous_done_cpus)) {
+			VCPU_CTR0(vm, vcpuid, "Calling rendezvous func");
+			(*vm->rendezvous_func)(vm, vcpuid, vm->rendezvous_arg);
+			CPU_SET(vcpuid, &vm->rendezvous_done_cpus);
+		}
+		if (CPU_CMP(&vm->rendezvous_req_cpus,
+		    &vm->rendezvous_done_cpus) == 0) {
+			VCPU_CTR0(vm, vcpuid, "Rendezvous completed");
+			vm_set_rendezvous_func(vm, NULL);
+			wakeup(&vm->rendezvous_func);
+			break;
+		}
+		RENDEZVOUS_CTR0(vm, vcpuid, "Wait for rendezvous completion");
+		mtx_sleep(&vm->rendezvous_func, &vm->rendezvous_mtx, 0,
+		    "vmrndv", 0);
+	}
+	mtx_unlock(&vm->rendezvous_mtx);
+}
+
 /*
  * Emulate a guest 'hlt' by sleeping until the vcpu is ready to run.
  */
@@ -874,9 +954,10 @@ vm_handle_hlt(struct vm *vm, int vcpuid, bool intr_disabled, bool *retu)
 {
 	struct vm_exit *vmexit;
 	struct vcpu *vcpu;
-	int t, timo;
+	int t, timo, spindown;
 
 	vcpu = &vm->vcpu[vcpuid];
+	spindown = 0;
 
 	vcpu_lock(vcpu);
 
@@ -888,7 +969,7 @@ vm_handle_hlt(struct vm *vm, int vcpuid, bool intr_disabled, bool *retu)
 	 * returned from VMRUN() and before we grabbed the vcpu lock.
 	 */
 	if (!vm_nmi_pending(vm, vcpuid) &&
-	    (intr_disabled || vlapic_pending_intr(vcpu->vlapic) < 0)) {
+	    (intr_disabled || !vlapic_pending_intr(vcpu->vlapic, NULL))) {
 		t = ticks;
 		vcpu_require_state_locked(vcpu, VCPU_SLEEPING);
 		if (vlapic_enabled(vcpu->vlapic)) {
@@ -903,16 +984,25 @@ vm_handle_hlt(struct vm *vm, int vcpuid, bool intr_disabled, bool *retu)
 			 * Spindown the vcpu if the apic is disabled and it
 			 * had entered the halted state.
 			 */
-			*retu = true;
-			vmexit = vm_exitinfo(vm, vcpuid);
-			vmexit->exitcode = VM_EXITCODE_SPINDOWN_CPU;
-			VCPU_CTR0(vm, vcpuid, "spinning down cpu");
+			spindown = 1;
 		}
 		vcpu_require_state_locked(vcpu, VCPU_FROZEN);
 		vmm_stat_incr(vm, vcpuid, VCPU_IDLE_TICKS, ticks - t);
 	}
 	vcpu_unlock(vcpu);
 
+	/*
+	 * Since 'vm_deactivate_cpu()' grabs a sleep mutex we must call it
+	 * outside the confines of the vcpu spinlock.
+	 */
+	if (spindown) {
+		*retu = true;
+		vmexit = vm_exitinfo(vm, vcpuid);
+		vmexit->exitcode = VM_EXITCODE_SPINDOWN_CPU;
+		vm_deactivate_cpu(vm, vcpuid);
+		VCPU_CTR0(vm, vcpuid, "spinning down cpu");
+	}
+
 	return (0);
 }
 
@@ -1042,7 +1132,7 @@ restart:
 
 	vcpu_require_state(vm, vcpuid, VCPU_RUNNING);
 	vcpu->hostcpu = curcpu;
-	error = VMRUN(vm->cookie, vcpuid, rip, pmap);
+	error = VMRUN(vm->cookie, vcpuid, rip, pmap, &vm->rendezvous_func);
 	vcpu->hostcpu = NOCPU;
 	vcpu_require_state(vm, vcpuid, VCPU_FROZEN);
 
@@ -1056,6 +1146,14 @@ restart:
 	if (error == 0) {
 		retu = false;
 		switch (vme->exitcode) {
+		case VM_EXITCODE_IOAPIC_EOI:
+			vioapic_process_eoi(vm, vcpuid,
+			    vme->u.ioapic_eoi.vector);
+			break;
+		case VM_EXITCODE_RENDEZVOUS:
+			vm_handle_rendezvous(vm, vcpuid);
+			error = 0;
+			break;
 		case VM_EXITCODE_HLT:
 			intr_disabled = ((vme->u.hlt.rflags & PSL_I) == 0);
 			error = vm_handle_hlt(vm, vcpuid, intr_disabled, &retu);
@@ -1111,7 +1209,7 @@ vm_inject_nmi(struct vm *vm, int vcpuid)
 	vcpu = &vm->vcpu[vcpuid];
 
 	vcpu->nmi_pending = 1;
-	vcpu_notify_event(vm, vcpuid);
+	vcpu_notify_event(vm, vcpuid, false);
 	return (0);
 }
 
@@ -1286,8 +1384,37 @@ void
 vm_activate_cpu(struct vm *vm, int vcpuid)
 {
 
-	if (vcpuid >= 0 && vcpuid < VM_MAXCPU)
-		CPU_SET(vcpuid, &vm->active_cpus);
+	KASSERT(vcpuid >= 0 && vcpuid < VM_MAXCPU,
+	    ("vm_activate_cpu: invalid vcpuid %d", vcpuid));
+	KASSERT(!CPU_ISSET(vcpuid, &vm->active_cpus),
+	    ("vm_activate_cpu: vcpuid %d is already active", vcpuid));
+
+	VCPU_CTR0(vm, vcpuid, "activated");
+	CPU_SET_ATOMIC(vcpuid, &vm->active_cpus);
+}
+
+static void
+vm_deactivate_cpu(struct vm *vm, int vcpuid)
+{
+
+	KASSERT(vcpuid >= 0 && vcpuid < VM_MAXCPU,
+	    ("vm_deactivate_cpu: invalid vcpuid %d", vcpuid));
+	KASSERT(CPU_ISSET(vcpuid, &vm->active_cpus),
+	    ("vm_deactivate_cpu: vcpuid %d is not active", vcpuid));
+
+	VCPU_CTR0(vm, vcpuid, "deactivated");
+	CPU_CLR_ATOMIC(vcpuid, &vm->active_cpus);
+
+	/*
+	 * If a vcpu rendezvous is in progress then it could be blocked
+	 * on 'vcpuid' - unblock it before disappearing forever.
+	 */
+	mtx_lock(&vm->rendezvous_mtx);
+	if (vm->rendezvous_func != NULL) {
+		VCPU_CTR0(vm, vcpuid, "unblock rendezvous after deactivation");
+		wakeup(&vm->rendezvous_func);
+	}
+	mtx_unlock(&vm->rendezvous_mtx);
 }
 
 cpuset_t
@@ -1339,7 +1466,7 @@ vm_set_x2apic_state(struct vm *vm, int vcpuid, enum x2apic_state state)
  *   to the host_cpu to cause the vcpu to trap into the hypervisor.
  */
 void
-vcpu_notify_event(struct vm *vm, int vcpuid)
+vcpu_notify_event(struct vm *vm, int vcpuid, bool lapic_intr)
 {
 	int hostcpu;
 	struct vcpu *vcpu;
@@ -1354,8 +1481,13 @@ vcpu_notify_event(struct vm *vm, int vcpuid)
 	} else {
 		if (vcpu->state != VCPU_RUNNING)
 			panic("invalid vcpu state %d", vcpu->state);
-		if (hostcpu != curcpu)
-			ipi_cpu(hostcpu, vmm_ipinum);
+		if (hostcpu != curcpu) {
+			if (lapic_intr)
+				vlapic_post_intr(vcpu->vlapic, hostcpu,
+				    vmm_ipinum);
+			else
+				ipi_cpu(hostcpu, vmm_ipinum);
+		}
 	}
 	vcpu_unlock(vcpu);
 }
@@ -1375,3 +1507,51 @@ vm_apicid2vcpuid(struct vm *vm, int apicid)
 	 */
 	return (apicid);
 }
+
+void
+vm_smp_rendezvous(struct vm *vm, int vcpuid, cpuset_t dest,
+    vm_rendezvous_func_t func, void *arg)
+{
+	int i;
+
+	/*
+	 * Enforce that this function is called without any locks
+	 */
+	WITNESS_WARN(WARN_PANIC, NULL, "vm_smp_rendezvous");
+	KASSERT(vcpuid == -1 || (vcpuid >= 0 && vcpuid < VM_MAXCPU),
+	    ("vm_smp_rendezvous: invalid vcpuid %d", vcpuid));
+
+restart:
+	mtx_lock(&vm->rendezvous_mtx);
+	if (vm->rendezvous_func != NULL) {
+		/*
+		 * If a rendezvous is already in progress then we need to
+		 * call the rendezvous handler in case this 'vcpuid' is one
+		 * of the targets of the rendezvous.
+		 */
+		RENDEZVOUS_CTR0(vm, vcpuid, "Rendezvous already in progress");
+		mtx_unlock(&vm->rendezvous_mtx);
+		vm_handle_rendezvous(vm, vcpuid);
+		goto restart;
+	}
+	KASSERT(vm->rendezvous_func == NULL, ("vm_smp_rendezvous: previous "
+	    "rendezvous is still in progress"));
+
+	RENDEZVOUS_CTR0(vm, vcpuid, "Initiating rendezvous");
+	vm->rendezvous_req_cpus = dest;
+	CPU_ZERO(&vm->rendezvous_done_cpus);
+	vm->rendezvous_arg = arg;
+	vm_set_rendezvous_func(vm, func);
+	mtx_unlock(&vm->rendezvous_mtx);
+
+	/*
+	 * Wake up any sleeping vcpus and trigger a VM-exit in any running
+	 * vcpus so they handle the rendezvous as soon as possible.
+	 */
+	for (i = 0; i < VM_MAXCPU; i++) {
+		if (CPU_ISSET(i, &dest))
+			vcpu_notify_event(vm, i, false);
+	}
+
+	vm_handle_rendezvous(vm, vcpuid);
+}