hyperv/vmbus: Busdma-fy Hypercall signal event input parameter.

MFC after:	1 week
Sponsored by:	Microsoft OSTC
Differential Revision:	https://reviews.freebsd.org/D6916

sys/dev/hyperv/include/hyperv.h

@@ -55,6 +55,7 @@
 
 #include <amd64/include/xen/synch_bitops.h>
 #include <amd64/include/atomic.h>
+#include <dev/hyperv/include/hyperv_busdma.h>
 
 typedef uint8_t	hv_bool_uint8_t;
 
@@ -528,20 +529,6 @@ typedef union {
 
 } __packed hv_vmbus_connection_id;
 
-/*
- * Definition of the hv_vmbus_signal_event hypercall input structure
- */
-typedef struct {
-	hv_vmbus_connection_id	connection_id;
-	uint16_t		flag_number;
-	uint16_t		rsvd_z;
-} __packed hv_vmbus_input_signal_event;
-
-typedef struct {
-	uint64_t			align8;
-	hv_vmbus_input_signal_event	event;
-} __packed hv_vmbus_input_signal_event_buffer;
-
 typedef struct hv_vmbus_channel {
 	TAILQ_ENTRY(hv_vmbus_channel)	list_entry;
 	struct hv_device*		device;
@@ -589,14 +576,8 @@ typedef struct hv_vmbus_channel {
 
 	boolean_t			is_dedicated_interrupt;
 
-	/*
-	 * Used as an input param for HV_CALL_SIGNAL_EVENT hypercall.
-	 */
-	hv_vmbus_input_signal_event_buffer	signal_event_buffer;
-	/*
-	 * 8-bytes aligned of the buffer above
-	 */
-	hv_vmbus_input_signal_event	*signal_event_param;
+	struct hypercall_sigevt_in	*ch_sigevt;
+	struct hyperv_dma		ch_sigevt_dma;
 
 	/*
 	 * From Win8, this field specifies the target virtual process

sys/dev/hyperv/include/hyperv_busdma.h

@@ -29,6 +29,10 @@
 #ifndef _HYPERV_BUSDMA_H_
 #define _HYPERV_BUSDMA_H_
 
+#include <sys/param.h>
+#include <sys/bus.h>
+#include <machine/bus.h>
+
 struct hyperv_dma {
 	bus_addr_t	hv_paddr;
 	bus_dma_tag_t	hv_dtag;

sys/dev/hyperv/vmbus/hv_channel.c

@@ -46,6 +46,7 @@ __FBSDID("$FreeBSD$");
 #include <vm/pmap.h>
 
 #include <dev/hyperv/vmbus/hv_vmbus_priv.h>
+#include <dev/hyperv/vmbus/hyperv_var.h>
 #include <dev/hyperv/vmbus/vmbus_reg.h>
 #include <dev/hyperv/vmbus/vmbus_var.h>
 
@@ -72,7 +73,7 @@ vmbus_channel_set_event(hv_vmbus_channel *channel)
 			(uint32_t *)&monitor_page->
 				trigger_group[channel->monitor_group].u.pending);
 	} else {
-		hv_vmbus_set_event(channel);
+		hypercall_signal_event(channel->ch_sigevt_dma.hv_paddr);
 	}
 
 }

sys/dev/hyperv/vmbus/hv_channel_mgmt.c

@@ -32,6 +32,7 @@
 #include <sys/mbuf.h>
 #include <sys/mutex.h>
 
+#include <dev/hyperv/include/hyperv_busdma.h>
 #include <dev/hyperv/vmbus/hv_vmbus_priv.h>
 #include <dev/hyperv/vmbus/vmbus_reg.h>
 #include <dev/hyperv/vmbus/vmbus_var.h>
@@ -327,23 +328,23 @@ vmbus_channel_on_offer_internal(struct vmbus_softc *sc,
 	 */
 	new_channel->batched_reading = TRUE;
 
-	new_channel->signal_event_param =
-	    (hv_vmbus_input_signal_event *)
-	    (HV_ALIGN_UP((unsigned long)
-		&new_channel->signal_event_buffer,
-		HV_HYPERCALL_PARAM_ALIGN));
-
- 	new_channel->signal_event_param->connection_id.as_uint32_t = 0;	
-	new_channel->signal_event_param->connection_id.u.id =
-	    HV_VMBUS_EVENT_CONNECTION_ID;
-	new_channel->signal_event_param->flag_number = 0;
-	new_channel->signal_event_param->rsvd_z = 0;
+	new_channel->ch_sigevt = hyperv_dmamem_alloc(
+	    bus_get_dma_tag(sc->vmbus_dev),
+	    HYPERCALL_SIGEVTIN_ALIGN, 0, sizeof(struct hypercall_sigevt_in),
+	    &new_channel->ch_sigevt_dma, BUS_DMA_WAITOK | BUS_DMA_ZERO);
+	if (new_channel->ch_sigevt == NULL) {
+		device_printf(sc->vmbus_dev, "sigevt alloc failed\n");
+		/* XXX */
+		mtx_destroy(&new_channel->sc_lock);
+		free(new_channel, M_DEVBUF);
+		return;
+	}
+	new_channel->ch_sigevt->hc_connid = VMBUS_CONNID_EVENT;
 
 	if (hv_vmbus_protocal_version != HV_VMBUS_VERSION_WS2008) {
 		new_channel->is_dedicated_interrupt =
 		    (offer->is_dedicated_interrupt != 0);
-		new_channel->signal_event_param->connection_id.u.id =
-		    offer->connection_id;
+		new_channel->ch_sigevt->hc_connid = offer->connection_id;
 	}
 
 	memcpy(&new_channel->offer_msg, offer,

sys/dev/hyperv/vmbus/hv_connection.c

@@ -158,16 +158,6 @@ vmbus_event_proc_compat(struct vmbus_softc *sc, int cpu)
 	}
 }
 
-/**
- * Send an event notification to the parent
- */
-int
-hv_vmbus_set_event(hv_vmbus_channel *channel)
-{
-
-	return hv_vmbus_signal_event(channel->signal_event_param);
-}
-
 void
 vmbus_on_channel_open(const struct hv_vmbus_channel *chan)
 {

sys/dev/hyperv/vmbus/hv_vmbus_priv.h

@@ -363,6 +363,5 @@ int			hv_vmbus_child_device_unregister(
  */
 int			hv_vmbus_connect(struct vmbus_softc *);
 int			hv_vmbus_disconnect(void);
-int			hv_vmbus_set_event(hv_vmbus_channel *channel);
 
 #endif  /* __HYPERV_PRIV_H__ */

sys/dev/hyperv/vmbus/hyperv.c

@@ -125,6 +125,13 @@ hypercall_post_message(bus_addr_t msg_paddr)
 	    HYPERCALL_POST_MESSAGE, msg_paddr, 0);
 }
 
+uint64_t
+hypercall_signal_event(bus_addr_t sigevt_paddr)
+{
+	return hypercall_md(hypercall_context.hc_addr,
+	    HYPERCALL_SIGNAL_EVENT, sigevt_paddr, 0);
+}
+
 /**
  * @brief Signal an event on the specified connection using the hypervisor
  * event IPC. (This involves a hypercall.)

sys/dev/hyperv/vmbus/hyperv_reg.h

@@ -148,6 +148,7 @@
  * Hypercall input values
  */
 #define HYPERCALL_POST_MESSAGE		0x005c
+#define HYPERCALL_SIGNAL_EVENT		0x005d
 
 /*
  * Hypercall input parameters
@@ -169,4 +170,15 @@ struct hypercall_postmsg_in {
 } __packed;
 CTASSERT(sizeof(struct hypercall_postmsg_in) == HYPERCALL_POSTMSGIN_SIZE);
 
+/*
+ * HYPERCALL_SIGNAL_EVENT
+ */
+#define HYPERCALL_SIGEVTIN_ALIGN	8
+
+struct hypercall_sigevt_in {
+	uint32_t	hc_connid;
+	uint16_t	hc_evtflag_ofs;
+	uint16_t	hc_rsvd;
+} __packed;
+
 #endif	/* !_HYPERV_REG_H_ */

sys/dev/hyperv/vmbus/hyperv_var.h

@@ -39,5 +39,6 @@ extern u_int	hyperv_features;
 extern u_int	hyperv_recommends;
 
 uint64_t	hypercall_post_message(bus_addr_t msg_paddr);
+uint64_t	hypercall_signal_event(bus_addr_t sigevt_paddr);
 
 #endif	/* !_HYPERV_VAR_H_ */

sys/dev/hyperv/vmbus/vmbus.c

@@ -69,12 +69,6 @@ __FBSDID("$FreeBSD$");
 #include <contrib/dev/acpica/include/acpi.h>
 #include "acpi_if.h"
 
-/*
- * NOTE: DO NOT CHANGE THESE
- */
-#define VMBUS_CONNID_MESSAGE		1
-#define VMBUS_CONNID_EVENT		2
-
 struct vmbus_msghc {
 	struct hypercall_postmsg_in	*mh_inprm;
 	struct hypercall_postmsg_in	mh_inprm_save;

sys/dev/hyperv/vmbus/vmbus_var.h

@@ -46,6 +46,12 @@
  */
 #define VMBUS_SINT_TIMER	4
 
+/*
+ * NOTE: DO NOT CHANGE THESE
+ */
+#define VMBUS_CONNID_MESSAGE		1
+#define VMBUS_CONNID_EVENT		2
+
 struct vmbus_pcpu_data {
 	u_long			*intr_cnt;	/* Hyper-V interrupt counter */
 	struct vmbus_message	*message;	/* shared messages */