From 3f1e1478db2d67098d98f2c3acf5a4946b7fb643 Mon Sep 17 00:00:00 2001 From: Cao jin Date: Wed, 28 Oct 2015 14:20:31 +0800 Subject: [PATCH] enable multi-function hot-add Enable PCIe device multi-function hot-add, just ensure function 0 is added last, then driver will get the notification to scan the slot. Signed-off-by: Cao jin Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/pci/pci.c | 40 +++++++++++++++++++++++++++++++++++++++- hw/pci/pci_host.c | 15 +++++++++++++++ hw/pci/pcie.c | 18 +++++++++--------- include/hw/pci/pci.h | 1 + 4 files changed, 64 insertions(+), 10 deletions(-) diff --git a/hw/pci/pci.c b/hw/pci/pci.c index b0bf54061f..168b9cc56b 100644 --- a/hw/pci/pci.c +++ b/hw/pci/pci.c @@ -847,6 +847,9 @@ static PCIDevice *do_pci_register_device(PCIDevice *pci_dev, PCIBus *bus, PCIConfigWriteFunc *config_write = pc->config_write; Error *local_err = NULL; AddressSpace *dma_as; + DeviceState *dev = DEVICE(pci_dev); + + pci_dev->bus = bus; if (devfn < 0) { for(devfn = bus->devfn_min ; devfn < ARRAY_SIZE(bus->devices); @@ -864,9 +867,17 @@ static PCIDevice *do_pci_register_device(PCIDevice *pci_dev, PCIBus *bus, PCI_SLOT(devfn), PCI_FUNC(devfn), name, bus->devices[devfn]->name); return NULL; + } else if (dev->hotplugged && + pci_get_function_0(pci_dev)) { + error_setg(errp, "PCI: slot %d function 0 already ocuppied by %s," + " new func %s cannot be exposed to guest.", + PCI_SLOT(devfn), + bus->devices[PCI_DEVFN(PCI_SLOT(devfn), 0)]->name, + name); + + return NULL; } - pci_dev->bus = bus; pci_dev->devfn = devfn; dma_as = pci_device_iommu_address_space(pci_dev); @@ -2454,6 +2465,33 @@ void pci_bus_get_w64_range(PCIBus *bus, Range *range) pci_for_each_device_under_bus(bus, pci_dev_get_w64, range); } +static bool pcie_has_upstream_port(PCIDevice *dev) +{ + PCIDevice *parent_dev = pci_bridge_get_device(dev->bus); + + /* Device associated with an upstream port. + * As there are several types of these, it's easier to check the + * parent device: upstream ports are always connected to + * root or downstream ports. + */ + return parent_dev && + pci_is_express(parent_dev) && + parent_dev->exp.exp_cap && + (pcie_cap_get_type(parent_dev) == PCI_EXP_TYPE_ROOT_PORT || + pcie_cap_get_type(parent_dev) == PCI_EXP_TYPE_DOWNSTREAM); +} + +PCIDevice *pci_get_function_0(PCIDevice *pci_dev) +{ + if(pcie_has_upstream_port(pci_dev)) { + /* With an upstream PCIe port, we only support 1 device at slot 0 */ + return pci_dev->bus->devices[0]; + } else { + /* Other bus types might support multiple devices at slots 0-31 */ + return pci_dev->bus->devices[PCI_DEVFN(PCI_SLOT(pci_dev->devfn), 0)]; + } +} + static const TypeInfo pci_device_type_info = { .name = TYPE_PCI_DEVICE, .parent = TYPE_DEVICE, diff --git a/hw/pci/pci_host.c b/hw/pci/pci_host.c index 3e26f9256c..49f59a5dbc 100644 --- a/hw/pci/pci_host.c +++ b/hw/pci/pci_host.c @@ -20,6 +20,7 @@ #include "hw/pci/pci.h" #include "hw/pci/pci_host.h" +#include "hw/pci/pci_bus.h" #include "trace.h" /* debug PCI */ @@ -52,6 +53,13 @@ void pci_host_config_write_common(PCIDevice *pci_dev, uint32_t addr, uint32_t limit, uint32_t val, uint32_t len) { assert(len <= 4); + /* non-zero functions are only exposed when function 0 is present, + * allowing direct removal of unexposed functions. + */ + if (pci_dev->qdev.hotplugged && !pci_get_function_0(pci_dev)) { + return; + } + trace_pci_cfg_write(pci_dev->name, PCI_SLOT(pci_dev->devfn), PCI_FUNC(pci_dev->devfn), addr, val); pci_dev->config_write(pci_dev, addr, val, MIN(len, limit - addr)); @@ -63,6 +71,13 @@ uint32_t pci_host_config_read_common(PCIDevice *pci_dev, uint32_t addr, uint32_t ret; assert(len <= 4); + /* non-zero functions are only exposed when function 0 is present, + * allowing direct removal of unexposed functions. + */ + if (pci_dev->qdev.hotplugged && !pci_get_function_0(pci_dev)) { + return ~0x0; + } + ret = pci_dev->config_read(pci_dev, addr, MIN(len, limit - addr)); trace_pci_cfg_read(pci_dev->name, PCI_SLOT(pci_dev->devfn), PCI_FUNC(pci_dev->devfn), addr, ret); diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c index a72d516e4f..32c65c27a4 100644 --- a/hw/pci/pcie.c +++ b/hw/pci/pcie.c @@ -249,16 +249,16 @@ void pcie_cap_slot_hotplug_cb(HotplugHandler *hotplug_dev, DeviceState *dev, return; } - /* TODO: multifunction hot-plug. - * Right now, only a device of function = 0 is allowed to be - * hot plugged/unplugged. + /* To enable multifunction hot-plug, we just ensure the function + * 0 added last. When function 0 is added, we set the sltsta and + * inform OS via event notification. */ - assert(PCI_FUNC(pci_dev->devfn) == 0); - - pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTSTA, - PCI_EXP_SLTSTA_PDS); - pcie_cap_slot_event(PCI_DEVICE(hotplug_dev), - PCI_EXP_HP_EV_PDC | PCI_EXP_HP_EV_ABP); + if (pci_get_function_0(pci_dev)) { + pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTSTA, + PCI_EXP_SLTSTA_PDS); + pcie_cap_slot_event(PCI_DEVICE(hotplug_dev), + PCI_EXP_HP_EV_PDC | PCI_EXP_HP_EV_ABP); + } } static void pcie_unplug_device(PCIBus *bus, PCIDevice *dev, void *opaque) diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h index f5e7fd818a..379b6e1a45 100644 --- a/include/hw/pci/pci.h +++ b/include/hw/pci/pci.h @@ -397,6 +397,7 @@ void pci_for_each_bus_depth_first(PCIBus *bus, void *(*begin)(PCIBus *bus, void *parent_state), void (*end)(PCIBus *bus, void *state), void *parent_state); +PCIDevice *pci_get_function_0(PCIDevice *pci_dev); /* Use this wrapper when specific scan order is not required. */ static inline -- 2.11.4.GIT