vmd/vmctl: Add ability to pause / unpause vms

With help from Ashwin Agrawal

ok reyk@ mlarkin@

9 files changed, 211 insertions, 34 deletions

diff --git a/usr.sbin/vmd/control.c b/usr.sbin/vmd/control.c
index 1e7eba2f0b3..08baa77cf0d 100644
--- a/usr.sbin/vmd/control.c
+++ b/usr.sbin/vmd/control.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: control.c,v 1.19 2017/05/04 19:41:58 reyk Exp $	*/
+/*	$OpenBSD: control.c,v 1.20 2017/07/09 00:51:40 pd Exp $	*/
 
 /*
  * Copyright (c) 2010-2015 Reyk Floeter <reyk@openbsd.org>
@@ -83,6 +83,8 @@ control_dispatch_vmd(int fd, struct privsep_proc *p, struct imsg *imsg)
 
 	switch (imsg->hdr.type) {
 	case IMSG_VMDOP_START_VM_RESPONSE:
+	case IMSG_VMDOP_PAUSE_VM_RESPONSE:
+	case IMSG_VMDOP_UNPAUSE_VM_RESPONSE:
 	case IMSG_VMDOP_TERMINATE_VM_RESPONSE:
 	case IMSG_VMDOP_GET_INFO_VM_DATA:
 	case IMSG_VMDOP_GET_INFO_VM_END_DATA:
@@ -366,6 +368,8 @@ control_dispatch_imsg(int fd, short event, void *arg)
 			log_setverbose(v);
 
 			/* FALLTHROUGH */
+		case IMSG_VMDOP_PAUSE_VM:
+		case IMSG_VMDOP_UNPAUSE_VM:
 		case IMSG_VMDOP_LOAD:
 		case IMSG_VMDOP_RELOAD:
 		case IMSG_CTL_RESET:
diff --git a/usr.sbin/vmd/i8253.c b/usr.sbin/vmd/i8253.c
index 5fa4d8a34da..ff33c0ecae2 100644
--- a/usr.sbin/vmd/i8253.c
+++ b/usr.sbin/vmd/i8253.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: i8253.c,v 1.15 2017/05/08 09:08:40 reyk Exp $ */
+/* $OpenBSD: i8253.c,v 1.16 2017/07/09 00:51:40 pd Exp $ */
 /*
  * Copyright (c) 2016 Mike Larkin <mlarkin@openbsd.org>
  *
@@ -314,6 +314,7 @@ i8253_reset(uint8_t chn)
 	evtimer_del(&i8253_channel[chn].timer);
 	timerclear(&tv);
 
+	i8253_channel[chn].in_use = 1;
 	tv.tv_usec = (i8253_channel[chn].start * NS_PER_TICK) / 1000;
 	evtimer_add(&i8253_channel[chn].timer, &tv);
 }
@@ -359,30 +360,37 @@ i8253_dump(int fd)
 int
 i8253_restore(int fd, uint32_t vm_id)
 {
+	int i;
 	log_debug("%s: restoring PIT", __func__);
 	if (atomicio(read, fd, &i8253_channel, sizeof(i8253_channel)) !=
 	    sizeof(i8253_channel)) {
 		log_warnx("%s: error reading PIT from fd", __func__);
 		return (-1);
 	}
-	memset(&i8253_channel[0].timer, 0, sizeof(struct event));
-	memset(&i8253_channel[1].timer, 0, sizeof(struct event));
-	memset(&i8253_channel[2].timer, 0, sizeof(struct event));
-	i8253_channel[0].vm_id = vm_id;
-	i8253_channel[1].vm_id = vm_id;
-	i8253_channel[2].vm_id = vm_id;
 
-	evtimer_set(&i8253_channel[0].timer, i8253_fire, &i8253_channel[0]);
-	evtimer_set(&i8253_channel[1].timer, i8253_fire, &i8253_channel[1]);
-	evtimer_set(&i8253_channel[2].timer, i8253_fire, &i8253_channel[2]);
-	i8253_reset(0);
+	for (i = 0; i < 3; i++) {
+		memset(&i8253_channel[i].timer, 0, sizeof(struct event));
+		i8253_channel[i].vm_id = vm_id;
+		evtimer_set(&i8253_channel[i].timer, i8253_fire,
+		    &i8253_channel[i]);
+		i8253_reset(i);
+	}
 	return (0);
 }
 
 void
 i8253_stop()
 {
-	evtimer_del(&i8253_channel[0].timer);
-	evtimer_del(&i8253_channel[1].timer);
-	evtimer_del(&i8253_channel[2].timer);
+	int i;
+	for (i = 0; i < 3; i++)
+		evtimer_del(&i8253_channel[i].timer);
+}
+
+void
+i8253_start()
+{
+	int i;
+	for (i = 0; i < 3; i++)
+		if(i8253_channel[i].in_use)
+			i8253_reset(i);
 }
diff --git a/usr.sbin/vmd/i8253.h b/usr.sbin/vmd/i8253.h
index 2bd6de8eef7..564dc5c5938 100644
--- a/usr.sbin/vmd/i8253.h
+++ b/usr.sbin/vmd/i8253.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: i8253.h,v 1.6 2017/05/08 09:08:40 reyk Exp $ */
+/* $OpenBSD: i8253.h,v 1.7 2017/07/09 00:51:40 pd Exp $ */
 /*
  * Copyright (c) 2016 Mike Larkin <mlarkin@openbsd.org>
  *
@@ -39,6 +39,7 @@ struct i8253_channel {
 	uint8_t rbs;		/* channel is in readback status mode */
 	struct event timer;	/* timer event for this counter */
 	uint32_t vm_id;		/* owning VM id */
+	int in_use;		/* denotes if this counter was ever used */
 };
 
 void i8253_init(uint32_t);
@@ -49,3 +50,4 @@ int i8253_restore(int, uint32_t);
 uint8_t vcpu_exit_i8253(struct vm_run_params *);
 void i8253_do_readback(uint32_t);
 void i8253_stop(void);
+void i8253_start(void);
diff --git a/usr.sbin/vmd/mc146818.c b/usr.sbin/vmd/mc146818.c
index 66656959556..2a81f17f75d 100644
--- a/usr.sbin/vmd/mc146818.c
+++ b/usr.sbin/vmd/mc146818.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: mc146818.c,v 1.14 2017/05/08 09:08:40 reyk Exp $ */
+/* $OpenBSD: mc146818.c,v 1.15 2017/07/09 00:51:40 pd Exp $ */
 /*
  * Copyright (c) 2016 Mike Larkin <mlarkin@openbsd.org>
  *
@@ -341,9 +341,6 @@ mc146818_restore(int fd, uint32_t vm_id)
 	memset(&rtc.per, 0, sizeof(struct event));
 	evtimer_set(&rtc.sec, rtc_fire1, NULL);
 	evtimer_set(&rtc.per, rtc_fireper, (void *)(intptr_t)rtc.vm_id);
-
-	evtimer_add(&rtc.per, &rtc.per_tv);
-	evtimer_add(&rtc.sec, &rtc.sec_tv);
 	return (0);
 }
 
@@ -353,3 +350,10 @@ mc146818_stop()
 	evtimer_del(&rtc.per);
 	evtimer_del(&rtc.sec);
 }
+
+void
+mc146818_start()
+{
+	evtimer_add(&rtc.per, &rtc.per_tv);
+	evtimer_add(&rtc.sec, &rtc.sec_tv);
+}
diff --git a/usr.sbin/vmd/mc146818.h b/usr.sbin/vmd/mc146818.h
index 8eadb47d0aa..f6e3509aa60 100644
--- a/usr.sbin/vmd/mc146818.h
+++ b/usr.sbin/vmd/mc146818.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: mc146818.h,v 1.4 2017/05/08 09:08:40 reyk Exp $ */
+/* $OpenBSD: mc146818.h,v 1.5 2017/07/09 00:51:40 pd Exp $ */
 /*
  * Copyright (c) 2016 Mike Larkin <mlarkin@openbsd.org>
  *
@@ -21,3 +21,4 @@ void dump_mc146818(void);
 int mc146818_dump(int);
 int mc146818_restore(int, uint32_t);
 void mc146818_stop(void);
+void mc146818_start(void);
diff --git a/usr.sbin/vmd/vm.c b/usr.sbin/vmd/vm.c
index 1c4e354422b..87b980d269c 100644
--- a/usr.sbin/vmd/vm.c
+++ b/usr.sbin/vmd/vm.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vm.c,v 1.20 2017/06/07 14:53:28 mlarkin Exp $	*/
+/*	$OpenBSD: vm.c,v 1.21 2017/07/09 00:51:40 pd Exp $	*/
 
 /*
  * Copyright (c) 2015 Mike Larkin <mlarkin@openbsd.org>
@@ -77,6 +77,8 @@ void vcpu_exit_inout(struct vm_run_params *);
 uint8_t vcpu_exit_pci(struct vm_run_params *);
 int vcpu_pic_intr(uint32_t, uint32_t, uint8_t);
 int loadfile_bios(FILE *, struct vcpu_reg_state *);
+void pause_vm(struct vm_create_params *);
+void unpause_vm(struct vm_create_params *);
 
 static struct vm_mem_range *find_gpa_range(struct vm_create_params *, paddr_t,
     size_t);
@@ -345,6 +347,7 @@ void
 vm_dispatch_vmm(int fd, short event, void *arg)
 {
 	struct vmd_vm		*vm = arg;
+	struct vmop_result	 vmr;
 	struct imsgev		*iev = &vm->vm_iev;
 	struct imsgbuf		*ibuf = &iev->ibuf;
 	struct imsg		 imsg;
@@ -391,6 +394,24 @@ vm_dispatch_vmm(int fd, short event, void *arg)
 			if (vmmci_ctl(VMMCI_REBOOT) == -1)
 				_exit(0);
 			break;
+		case IMSG_VMDOP_PAUSE_VM:
+			vmr.vmr_result = 0;
+			vmr.vmr_id = vm->vm_vmid;
+			pause_vm(&vm->vm_params.vmc_params);
+			imsg_compose_event(&vm->vm_iev,
+			    IMSG_VMDOP_PAUSE_VM_RESPONSE,
+			    imsg.hdr.peerid, imsg.hdr.pid, -1, &vmr,
+			    sizeof(vmr));
+			break;
+		case IMSG_VMDOP_UNPAUSE_VM:
+			vmr.vmr_result = 0;
+			vmr.vmr_id = vm->vm_vmid;
+			unpause_vm(&vm->vm_params.vmc_params);
+			imsg_compose_event(&vm->vm_iev,
+			    IMSG_VMDOP_UNPAUSE_VM_RESPONSE,
+			    imsg.hdr.peerid, imsg.hdr.pid, -1, &vmr,
+			    sizeof(vmr));
+			break;
 		default:
 			fatalx("%s: got invalid imsg %d from %s",
 			    __func__, imsg.hdr.type,
@@ -427,6 +448,37 @@ vm_shutdown(unsigned int cmd)
 	_exit(0);
 }
 
+void
+pause_vm(struct vm_create_params *vcp)
+{
+	if (current_vm->vm_paused)
+		return;
+
+	current_vm->vm_paused = 1;
+
+	/* XXX: vcpu_run_loop is running in another thread and we have to wait
+	 * for the vm to exit before returning */
+	sleep(1);
+
+	i8253_stop();
+	mc146818_stop();
+}
+
+void
+unpause_vm(struct vm_create_params *vcp)
+{
+	unsigned int n;
+	if (!current_vm->vm_paused)
+		return;
+
+	current_vm->vm_paused = 0;
+
+	i8253_start();
+	mc146818_start();
+	for (n = 0; n <= vcp->vcp_ncpus; n++)
+		pthread_cond_broadcast(&vcpu_run_cond[n]);
+}
+
 /*
  * vcpu_reset
  *
@@ -921,20 +973,37 @@ vcpu_run_loop(void *arg)
 			return ((void *)ret);
 		}
 
-		/* If we are halted, wait */
+		/* If we are halted or paused, wait */
 		if (vcpu_hlt[n]) {
-			ret = pthread_cond_wait(&vcpu_run_cond[n],
-			    &vcpu_run_mtx[n]);
-
-			if (ret) {
-				log_warnx("%s: can't wait on cond (%d)",
-				    __func__, (int)ret);
-				(void)pthread_mutex_unlock(&vcpu_run_mtx[n]);
-				break;
+			while (current_vm->vm_paused == 1) {
+				ret = pthread_cond_wait(&vcpu_run_cond[n],
+				    &vcpu_run_mtx[n]);
+				if (ret) {
+					log_warnx(
+					    "%s: can't wait on cond (%d)",
+					    __func__, (int)ret);
+					(void)pthread_mutex_unlock(
+					    &vcpu_run_mtx[n]);
+					break;
+				}
+			}
+			if (vcpu_hlt[n]) {
+				ret = pthread_cond_wait(&vcpu_run_cond[n],
+				    &vcpu_run_mtx[n]);
+
+				if (ret) {
+					log_warnx(
+					    "%s: can't wait on cond (%d)",
+					    __func__, (int)ret);
+					(void)pthread_mutex_unlock(
+					    &vcpu_run_mtx[n]);
+					break;
+				}
 			}
 		}
 
 		ret = pthread_mutex_unlock(&vcpu_run_mtx[n]);
+
 		if (ret) {
 			log_warnx("%s: can't unlock mutex on cond (%d)",
 			    __func__, (int)ret);
diff --git a/usr.sbin/vmd/vmd.c b/usr.sbin/vmd/vmd.c
index 440d64f87de..ca332ae3f28 100644
--- a/usr.sbin/vmd/vmd.c
+++ b/usr.sbin/vmd/vmd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vmd.c,v 1.62 2017/05/29 07:15:22 mlarkin Exp $	*/
+/*	$OpenBSD: vmd.c,v 1.63 2017/07/09 00:51:40 pd Exp $	*/
 
 /*
  * Copyright (c) 2015 Reyk Floeter <reyk@openbsd.org>
@@ -163,6 +163,22 @@ vmd_dispatch_control(int fd, struct privsep_proc *p, struct imsg *imsg)
 		proc_forward_imsg(ps, imsg, PROC_PRIV, -1);
 		cmd = IMSG_CTL_OK;
 		break;
+	case IMSG_VMDOP_PAUSE_VM:
+	case IMSG_VMDOP_UNPAUSE_VM:
+		IMSG_SIZE_CHECK(imsg, &vid);
+		memcpy(&vid, imsg->data, sizeof(vid));
+		if (vid.vid_id == 0) {
+			if ((vm = vm_getbyname(vid.vid_name)) == NULL) {
+				res = ENOENT;
+				cmd = IMSG_VMDOP_PAUSE_VM_RESPONSE;
+				break;
+			} else {
+				vid.vid_id = vm->vm_vmid;
+			}
+		}
+		proc_compose_imsg(ps, PROC_VMM, -1, imsg->hdr.type,
+		    imsg->hdr.peerid, -1, &vid, sizeof(vid));
+		break;
 	default:
 		return (-1);
 	}
@@ -200,6 +216,30 @@ vmd_dispatch_vmm(int fd, struct privsep_proc *p, struct imsg *imsg)
 	struct vmop_info_result	 vir;
 
 	switch (imsg->hdr.type) {
+	case IMSG_VMDOP_PAUSE_VM_RESPONSE:
+		IMSG_SIZE_CHECK(imsg, &vmr);
+		memcpy(&vmr, imsg->data, sizeof(vmr));
+		if ((vm = vm_getbyvmid(vmr.vmr_id)) == NULL)
+			break;
+		proc_compose_imsg(ps, PROC_CONTROL, -1,
+		    imsg->hdr.type, imsg->hdr.peerid, -1,
+		    imsg->data, sizeof(imsg->data));
+		log_info("%s: paused vm %d successfully",
+		    vm->vm_params.vmc_params.vcp_name,
+		    vm->vm_vmid);
+		break;
+	case IMSG_VMDOP_UNPAUSE_VM_RESPONSE:
+		IMSG_SIZE_CHECK(imsg, &vmr);
+		memcpy(&vmr, imsg->data, sizeof(vmr));
+		if ((vm = vm_getbyvmid(vmr.vmr_id)) == NULL)
+			break;
+		proc_compose_imsg(ps, PROC_CONTROL, -1,
+		    imsg->hdr.type, imsg->hdr.peerid, -1,
+		    imsg->data, sizeof(imsg->data));
+		log_info("%s: unpaused vm %d successfully.",
+		    vm->vm_params.vmc_params.vcp_name,
+		    vm->vm_vmid);
+		break;
 	case IMSG_VMDOP_START_VM_RESPONSE:
 		IMSG_SIZE_CHECK(imsg, &vmr);
 		memcpy(&vmr, imsg->data, sizeof(vmr));
@@ -869,6 +909,7 @@ vm_register(struct privsep *ps, struct vmop_create_params *vmc,
 	vcp = &vmc->vmc_params;
 	vm->vm_pid = -1;
 	vm->vm_tty = -1;
+	vm->vm_paused = 0;
 
 	for (i = 0; i < vcp->vcp_ndisks; i++)
 		vm->vm_disks[i] = -1;
diff --git a/usr.sbin/vmd/vmd.h b/usr.sbin/vmd/vmd.h
index be621835eaa..0cfd4cf546c 100644
--- a/usr.sbin/vmd/vmd.h
+++ b/usr.sbin/vmd/vmd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vmd.h,v 1.56 2017/06/12 13:41:24 deraadt Exp $	*/
+/*	$OpenBSD: vmd.h,v 1.57 2017/07/09 00:51:40 pd Exp $	*/
 
 /*
  * Copyright (c) 2015 Mike Larkin <mlarkin@openbsd.org>
@@ -65,6 +65,10 @@ enum imsg_type {
 	IMSG_VMDOP_START_VM_IF,
 	IMSG_VMDOP_START_VM_END,
 	IMSG_VMDOP_START_VM_RESPONSE,
+	IMSG_VMDOP_PAUSE_VM,
+	IMSG_VMDOP_PAUSE_VM_RESPONSE,
+	IMSG_VMDOP_UNPAUSE_VM,
+	IMSG_VMDOP_UNPAUSE_VM_RESPONSE,
 	IMSG_VMDOP_TERMINATE_VM_REQUEST,
 	IMSG_VMDOP_TERMINATE_VM_RESPONSE,
 	IMSG_VMDOP_TERMINATE_VM_EVENT,
@@ -189,6 +193,7 @@ struct vmd_vm {
 	struct imsgev		 vm_iev;
 	int			 vm_shutdown;
 	uid_t			 vm_uid;
+	int			 vm_paused;
 
 	TAILQ_ENTRY(vmd_vm)	 vm_entry;
 };
diff --git a/usr.sbin/vmd/vmm.c b/usr.sbin/vmd/vmm.c
index 3b0a453032b..2e992d6cb15 100644
--- a/usr.sbin/vmd/vmm.c
+++ b/usr.sbin/vmd/vmm.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vmm.c,v 1.69 2017/04/21 07:03:26 reyk Exp $	*/
+/*	$OpenBSD: vmm.c,v 1.70 2017/07/09 00:51:40 pd Exp $	*/
 
 /*
  * Copyright (c) 2015 Mike Larkin <mlarkin@openbsd.org>
@@ -105,6 +105,7 @@ vmm_dispatch_parent(int fd, struct privsep_proc *p, struct imsg *imsg)
 	int			 res = 0, cmd = 0, verbose;
 	struct vmd_vm		*vm = NULL;
 	struct vm_terminate_params vtp;
+	struct vmop_id vid;
 	struct vmop_result	 vmr;
 	uint32_t		 id = 0;
 	unsigned int		 mode;
@@ -202,6 +203,33 @@ vmm_dispatch_parent(int fd, struct privsep_proc *p, struct imsg *imsg)
 			    -1, &verbose, sizeof(verbose));
 		}
 		break;
+	case IMSG_VMDOP_PAUSE_VM:
+		IMSG_SIZE_CHECK(imsg, &vid);
+		memcpy(&vid, imsg->data, sizeof(vid));
+		id = vid.vid_id;
+		vm = vm_getbyvmid(id);
+		if ((vm = vm_getbyvmid(id)) == NULL) {
+			res = ENOENT;
+			cmd = IMSG_VMDOP_PAUSE_VM_RESPONSE;
+			break;
+		}
+		imsg_compose_event(&vm->vm_iev,
+		    imsg->hdr.type, imsg->hdr.peerid, imsg->hdr.pid,
+		    imsg->fd, &vid, sizeof(vid));
+		break;
+	case IMSG_VMDOP_UNPAUSE_VM:
+		IMSG_SIZE_CHECK(imsg, &vid);
+		memcpy(&vid, imsg->data, sizeof(vid));
+		id = vid.vid_id;
+		if ((vm = vm_getbyvmid(id)) == NULL) {
+			res = ENOENT;
+			cmd = IMSG_VMDOP_UNPAUSE_VM_RESPONSE;
+			break;
+		}
+		imsg_compose_event(&vm->vm_iev,
+		    imsg->hdr.type, imsg->hdr.peerid, imsg->hdr.pid,
+		    imsg->fd, &vid, sizeof(vid));
+		break;
 	default:
 		return (-1);
 	}
@@ -217,6 +245,8 @@ vmm_dispatch_parent(int fd, struct privsep_proc *p, struct imsg *imsg)
 		}
 		if (id == 0)
 			id = imsg->hdr.peerid;
+	case IMSG_VMDOP_PAUSE_VM_RESPONSE:
+	case IMSG_VMDOP_UNPAUSE_VM_RESPONSE:
 	case IMSG_VMDOP_TERMINATE_VM_RESPONSE:
 		memset(&vmr, 0, sizeof(vmr));
 		vmr.vmr_result = res;
@@ -354,6 +384,7 @@ vmm_dispatch_vm(int fd, short event, void *arg)
 	struct imsgbuf		*ibuf = &iev->ibuf;
 	struct imsg		 imsg;
 	ssize_t			 n;
+	unsigned int		 i;
 
 	if (event & EV_READ) {
 		if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN)
@@ -392,6 +423,18 @@ vmm_dispatch_vm(int fd, short event, void *arg)
 		case IMSG_VMDOP_VM_REBOOT:
 			vm->vm_shutdown = 0;
 			break;
+		case IMSG_VMDOP_PAUSE_VM_RESPONSE:
+		case IMSG_VMDOP_UNPAUSE_VM_RESPONSE:
+			for (i = 0; i < sizeof(procs); i++) {
+				if (procs[i].p_id == PROC_PARENT) {
+					proc_forward_imsg(procs[i].p_ps,
+							&imsg, PROC_PARENT,
+							-1);
+					break;
+				}
+			}
+			break;
+
 		default:
 			fatalx("%s: got invalid imsg %d from %s",
 			    __func__, imsg.hdr.type,