From: David Woodhouse <d...@amazon.co.uk> It calls an internal close_port() helper which will also be used from EVTCHNOP_reset and will actually do the work to disconnect/unbind a port once any of that is actually implemented in the first place.
That in turn calls a free_port() internal function which will be in error paths after allocation. Signed-off-by: David Woodhouse <d...@amazon.co.uk> --- hw/i386/kvm/xen_evtchn.c | 51 +++++++++++++++++++++++++++++++++++++++ hw/i386/kvm/xen_evtchn.h | 2 ++ target/i386/kvm/xen-emu.c | 12 +++++++++ 3 files changed, 65 insertions(+) diff --git a/hw/i386/kvm/xen_evtchn.c b/hw/i386/kvm/xen_evtchn.c index c162be86c7..3ccf72d78b 100644 --- a/hw/i386/kvm/xen_evtchn.c +++ b/hw/i386/kvm/xen_evtchn.c @@ -252,3 +252,54 @@ int xen_evtchn_status_op(struct evtchn_status *status) qemu_mutex_unlock(&s->port_lock); return 0; } + +static void free_port(XenEvtchnState *s, evtchn_port_t port) +{ + s->port_table[port].type = EVTCHNSTAT_closed; + s->port_table[port].type_val = 0; + s->port_table[port].vcpu = 0; + + if (s->nr_ports == port + 1) { + do { + s->nr_ports--; + } while (s->port_table[s->nr_ports - 1].type == EVTCHNSTAT_closed); + } +} + +static int close_port(XenEvtchnState *s, evtchn_port_t port) +{ + XenEvtchnPort *p = &s->port_table[port]; + + switch (p->type) { + case EVTCHNSTAT_closed: + return -ENOENT; + + default: + break; + } + + free_port(s, port); + return 0; +} + +int xen_evtchn_close_op(struct evtchn_close *close) +{ + XenEvtchnState *s = xen_evtchn_singleton; + int ret; + + if (!s) { + return -ENOTSUP; + } + + if (!valid_port(close->port)) { + return -EINVAL; + } + + qemu_mutex_lock(&s->port_lock); + + ret = close_port(s, close->port); + + qemu_mutex_unlock(&s->port_lock); + + return ret; +} diff --git a/hw/i386/kvm/xen_evtchn.h b/hw/i386/kvm/xen_evtchn.h index 76467636ee..cb3924941a 100644 --- a/hw/i386/kvm/xen_evtchn.h +++ b/hw/i386/kvm/xen_evtchn.h @@ -16,6 +16,8 @@ void xen_evtchn_create(void); int xen_evtchn_set_callback_param(uint64_t param); struct evtchn_status; +struct evtchn_close; int xen_evtchn_status_op(struct evtchn_status *status); +int xen_evtchn_close_op(struct evtchn_close *close); #endif /* QEMU_XEN_EVTCHN_H */ diff --git a/target/i386/kvm/xen-emu.c b/target/i386/kvm/xen-emu.c index 249cb88ec8..a81dbf5b63 100644 --- a/target/i386/kvm/xen-emu.c +++ b/target/i386/kvm/xen-emu.c @@ -790,6 +790,18 @@ static bool kvm_xen_hcall_evtchn_op(struct kvm_xen_exit *exit, X86CPU *cpu, } break; } + case EVTCHNOP_close: { + struct evtchn_close close; + + qemu_build_assert(sizeof(close) == 4); + if (kvm_copy_from_gva(cs, arg, &close, sizeof(close))) { + err = -EFAULT; + break; + } + + err = xen_evtchn_close_op(&close); + break; + } default: return false; } -- 2.35.3