KVM: keep track of running ioctls

Using the new accel-blocker API, mark where ioctls are being called
in KVM. Next, we will implement the critical section that will take
care of performing memslots modifications atomically, therefore
preventing any new ioctl from running and allowing the running ones
to finish.

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20221111154758.1372674-3-eesposit@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index e86c33e0e612ac72c3da8eebd32dbd01d7dea5c2..8760d55002cc59c6838806ebf3eaaa3e867df79b 100644 (file)
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -2310,6 +2310,7 @@ static int kvm_init(MachineState *ms)
     assert(TARGET_PAGE_SIZE <= qemu_real_host_page_size());
 
     s->sigmask_len = 8;
+    accel_blocker_init();
 
 #ifdef KVM_CAP_SET_GUEST_DEBUG
     QTAILQ_INIT(&s->kvm_sw_breakpoints);
@@ -3014,7 +3015,9 @@ int kvm_vm_ioctl(KVMState *s, int type, ...)
     va_end(ap);
 
     trace_kvm_vm_ioctl(type, arg);
+    accel_ioctl_begin();
     ret = ioctl(s->vmfd, type, arg);
+    accel_ioctl_end();
     if (ret == -1) {
         ret = -errno;
     }
@@ -3032,7 +3035,9 @@ int kvm_vcpu_ioctl(CPUState *cpu, int type, ...)
     va_end(ap);
 
     trace_kvm_vcpu_ioctl(cpu->cpu_index, type, arg);
+    accel_cpu_ioctl_begin(cpu);
     ret = ioctl(cpu->kvm_fd, type, arg);
+    accel_cpu_ioctl_end(cpu);
     if (ret == -1) {
         ret = -errno;
     }
@@ -3050,7 +3055,9 @@ int kvm_device_ioctl(int fd, int type, ...)
     va_end(ap);
 
     trace_kvm_device_ioctl(fd, type, arg);
+    accel_ioctl_begin();
     ret = ioctl(fd, type, arg);
+    accel_ioctl_end();
     if (ret == -1) {
         ret = -errno;
     }