To be used in further patch to identify the device hot-plugged into pcie-root-port.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@yandex-team.ru> Reviewed-by: Anton Kuchin <antonkuc...@yandex-team.ru> --- include/hw/pci/pci.h | 1 + hw/pci/pci.c | 33 +++++++++++++++++++++++++++++++++ 2 files changed, 34 insertions(+) diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h index d5a40cd058..b6c9c44527 100644 --- a/include/hw/pci/pci.h +++ b/include/hw/pci/pci.h @@ -341,6 +341,7 @@ void pci_for_each_device_under_bus_reverse(PCIBus *bus, void pci_for_each_bus_depth_first(PCIBus *bus, pci_bus_ret_fn begin, pci_bus_fn end, void *parent_state); PCIDevice *pci_get_function_0(PCIDevice *pci_dev); +PCIDevice *pci_find_the_only_child(PCIBus *bus, int bus_num, Error **errp); /* Use this wrapper when specific scan order is not required. */ static inline diff --git a/hw/pci/pci.c b/hw/pci/pci.c index 208c16f450..34fd1fb5b8 100644 --- a/hw/pci/pci.c +++ b/hw/pci/pci.c @@ -1771,6 +1771,39 @@ void pci_for_each_device(PCIBus *bus, int bus_num, } } +typedef struct TheOnlyChild { + PCIDevice *dev; + int count; +} TheOnlyChild; + +static void the_only_child_fn(PCIBus *bus, PCIDevice *dev, void *opaque) +{ + TheOnlyChild *s = opaque; + + s->dev = dev; + s->count++; +} + +PCIDevice *pci_find_the_only_child(PCIBus *bus, int bus_num, Error **errp) +{ + TheOnlyChild res = {0}; + + pci_for_each_device(bus, bus_num, the_only_child_fn, &res); + + if (!res.dev) { + assert(res.count == 0); + error_setg(errp, "No child devices found"); + return NULL; + } + + if (res.count > 1) { + error_setg(errp, "Several child devices found"); + return NULL; + } + + return res.dev; +} + const pci_class_desc *get_class_desc(int class) { const pci_class_desc *desc; -- 2.34.1