Add handling of SIGNAL_EVENT hypercall. For that, provide an interface
to associate an EventNotifier with an event connection number, so that
it's signaled when the SIGNAL_EVENT hypercall with the matching
connection ID is called by the guest.
Support for using KVM functionality for this will be added in a followup
patch.
Signed-off-by: Roman Kagan <rka...@virtuozzo.com>
---
include/hw/hyperv/hyperv-proto.h | 1 +
include/hw/hyperv/hyperv.h | 13 +++++
hw/hyperv/hyperv.c | 93 ++++++++++++++++++++++++++++++++
target/i386/hyperv.c | 10 ++--
4 files changed, 113 insertions(+), 4 deletions(-)
diff --git a/include/hw/hyperv/hyperv-proto.h b/include/hw/hyperv/hyperv-proto.h
index 2dc78eeafb..21dc28aee9 100644
--- a/include/hw/hyperv/hyperv-proto.h
+++ b/include/hw/hyperv/hyperv-proto.h
@@ -21,6 +21,7 @@
#define HV_STATUS_INVALID_ALIGNMENT 4
#define HV_STATUS_INVALID_PARAMETER 5
#define HV_STATUS_INSUFFICIENT_MEMORY 11
+#define HV_STATUS_INVALID_PORT_ID 17
#define HV_STATUS_INVALID_CONNECTION_ID 18
#define HV_STATUS_INSUFFICIENT_BUFFERS 19
diff --git a/include/hw/hyperv/hyperv.h b/include/hw/hyperv/hyperv.h
index 757c85eb8f..df92ed7e66 100644
--- a/include/hw/hyperv/hyperv.h
+++ b/include/hw/hyperv/hyperv.h
@@ -39,6 +39,19 @@ int hyperv_post_msg(HvSintRoute *sint_route, struct
hyperv_message *msg);
*/
int hyperv_set_event_flag(HvSintRoute *sint_route, unsigned eventno);
+/*
+ * Associate @notifier with the event connection @conn_id, such that @notifier
+ * is signaled when the guest executes HV_SIGNAL_EVENT hypercall on @conn_id.
+ * If @notifier is NULL clear the association.
+ */
+int hyperv_set_event_flag_handler(uint32_t conn_id, EventNotifier *notifier);
+
+/*
+ * Process HV_SIGNAL_EVENT hypercall: signal the EventNotifier associated with
+ * the connection as specified in @param.
+ */
+uint16_t hyperv_hcall_signal_event(uint64_t param, bool fast);
+
static inline uint32_t hyperv_vp_index(CPUState *cs)
{
return cs->cpu_index;
diff --git a/hw/hyperv/hyperv.c b/hw/hyperv/hyperv.c
index 0b28e7922c..5bb5126393 100644
--- a/hw/hyperv/hyperv.c
+++ b/hw/hyperv/hyperv.c
@@ -13,6 +13,9 @@
#include "exec/address-spaces.h"
#include "sysemu/kvm.h"
#include "qemu/bitops.h"
+#include "qemu/queue.h"
+#include "qemu/rcu.h"
+#include "qemu/rcu_queue.h"
#include "hw/hyperv/hyperv.h"
typedef struct SynICState {
@@ -450,3 +453,93 @@ int hyperv_sint_route_set_sint(HvSintRoute *sint_route)
{
return event_notifier_set(&sint_route->sint_set_notifier);
}
+
+typedef struct EventFlagHandler {
+ struct rcu_head rcu;
+ QLIST_ENTRY(EventFlagHandler) link;
+ uint32_t conn_id;
+ EventNotifier *notifier;
+} EventFlagHandler;
+
+static QLIST_HEAD(, EventFlagHandler) event_flag_handlers;
+static QemuMutex handlers_mutex;
+
+static void __attribute__((constructor)) hv_init(void)
+{
+ QLIST_INIT(&event_flag_handlers);
+ qemu_mutex_init(&handlers_mutex);
+}
+
+int hyperv_set_event_flag_handler(uint32_t conn_id, EventNotifier *notifier)
+{
+ int ret;
+ EventFlagHandler *handler;
+
+ qemu_mutex_lock(&handlers_mutex);
+ QLIST_FOREACH(handler, &event_flag_handlers, link) {
+ if (handler->conn_id == conn_id) {
+ if (notifier) {
+ ret = -EEXIST;
+ } else {
+ QLIST_REMOVE_RCU(handler, link);
+ g_free_rcu(handler, rcu);
+ ret = 0;
+ }
+ goto unlock;
+ }
+ }
+
+ if (notifier) {
+ handler = g_new(EventFlagHandler, 1);
+ handler->conn_id = conn_id;
+ handler->notifier = notifier;
+ QLIST_INSERT_HEAD_RCU(&event_flag_handlers, handler, link);
+ ret = 0;
+ } else {
+ ret = -ENOENT;
+ }
+unlock:
+ qemu_mutex_unlock(&handlers_mutex);
+ return ret;
+}
+
+uint16_t hyperv_hcall_signal_event(uint64_t param, bool fast)
+{
+ uint16_t ret;
+ EventFlagHandler *handler;
+
+ if (unlikely(!fast)) {
+ hwaddr addr = param;
+
+ if (addr & (__alignof__(addr) - 1)) {
+ return HV_STATUS_INVALID_ALIGNMENT;
+ }
+
+ param = ldq_phys(&address_space_memory, addr);
+ }
+
+ /*
+ * Per spec, bits 32-47 contain the extra "flag number". However, we
+ * have no use for it, and in all known usecases it is zero, so just
+ * report lookup failure if it isn't.
+ */
+ if (param & 0xffff00000000ULL) {
+ return HV_STATUS_INVALID_PORT_ID;
+ }
+ /* remaining bits are reserved-zero */
+ if (param & ~HV_CONNECTION_ID_MASK) {
+ return HV_STATUS_INVALID_HYPERCALL_INPUT;
+ }
+
+ ret = HV_STATUS_INVALID_CONNECTION_ID;
+ rcu_read_lock();
+ QLIST_FOREACH_RCU(handler, &event_flag_handlers, link) {
+ if (handler->conn_id == param) {
+ event_notifier_set(handler->notifier);
+ ret = 0;
+ break;
+ }
+ }
+ rcu_read_unlock();
+ return ret;
+}
diff --git a/target/i386/hyperv.c b/target/i386/hyperv.c
index 3f76c3e266..96b3b5ad7f 100644
--- a/target/i386/hyperv.c
+++ b/target/i386/hyperv.c
@@ -79,16 +79,18 @@ int kvm_hv_handle_exit(X86CPU *cpu, struct kvm_hyperv_exit
*exit)
return 0;
case KVM_EXIT_HYPERV_HCALL: {
- uint16_t code;
+ uint16_t code = exit->u.hcall.input & 0xffff;
+ bool fast = exit->u.hcall.input & HV_HYPERCALL_FAST;
+ uint64_t param = exit->u.hcall.params[0];
- code = exit->u.hcall.input & 0xffff;
switch (code) {
- case HV_POST_MESSAGE:
case HV_SIGNAL_EVENT:
+ exit->u.hcall.result = hyperv_hcall_signal_event(param, fast);
+ break;
default:
exit->u.hcall.result = HV_STATUS_INVALID_HYPERCALL_CODE;
- return 0;
}
+ return 0;
}
default:
return -1;
--
2.17.1
