From 2d64b7bbb2a2e945635633486ef9a060cb2c89bc Mon Sep 17 00:00:00 2001 From: Xingang Wang Date: Thu, 8 Jul 2021 12:55:11 +0000 Subject: [PATCH] hw/pci/pci_host: Allow PCI host to bypass iommu Add a new bypass_iommu property for PCI host and use it to check whether devices attached to the PCI root bus will bypass iommu. In pci_device_iommu_address_space(), check the property and avoid getting iommu address space for devices bypass iommu. Signed-off-by: Xingang Wang Reviewed-by: Eric Auger Message-Id: <1625748919-52456-2-git-send-email-wangxingang5@huawei.com> Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/pci/pci.c | 18 +++++++++++++++++- hw/pci/pci_host.c | 1 + include/hw/pci/pci.h | 1 + include/hw/pci/pci_host.h | 1 + 4 files changed, 20 insertions(+), 1 deletion(-) diff --git a/hw/pci/pci.c b/hw/pci/pci.c index 377084f1a8..27d588e268 100644 --- a/hw/pci/pci.c +++ b/hw/pci/pci.c @@ -416,6 +416,22 @@ const char *pci_root_bus_path(PCIDevice *dev) return rootbus->qbus.name; } +bool pci_bus_bypass_iommu(PCIBus *bus) +{ + PCIBus *rootbus = bus; + PCIHostState *host_bridge; + + if (!pci_bus_is_root(bus)) { + rootbus = pci_device_root_bus(bus->parent_dev); + } + + host_bridge = PCI_HOST_BRIDGE(rootbus->qbus.parent); + + assert(host_bridge->bus == rootbus); + + return host_bridge->bypass_iommu; +} + static void pci_root_bus_init(PCIBus *bus, DeviceState *parent, MemoryRegion *address_space_mem, MemoryRegion *address_space_io, @@ -2718,7 +2734,7 @@ AddressSpace *pci_device_iommu_address_space(PCIDevice *dev) iommu_bus = parent_bus; } - if (iommu_bus && iommu_bus->iommu_fn) { + if (!pci_bus_bypass_iommu(bus) && iommu_bus && iommu_bus->iommu_fn) { return iommu_bus->iommu_fn(bus, iommu_bus->iommu_opaque, devfn); } return &address_space_memory; diff --git a/hw/pci/pci_host.c b/hw/pci/pci_host.c index 8ca5fadcbd..cf02f0d6a5 100644 --- a/hw/pci/pci_host.c +++ b/hw/pci/pci_host.c @@ -222,6 +222,7 @@ const VMStateDescription vmstate_pcihost = { static Property pci_host_properties_common[] = { DEFINE_PROP_BOOL("x-config-reg-migration-enabled", PCIHostState, mig_enabled, true), + DEFINE_PROP_BOOL("bypass-iommu", PCIHostState, bypass_iommu, false), DEFINE_PROP_END_OF_LIST(), }; diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h index 6be4e0c460..f4d51b672b 100644 --- a/include/hw/pci/pci.h +++ b/include/hw/pci/pci.h @@ -480,6 +480,7 @@ void pci_for_each_bus(PCIBus *bus, PCIBus *pci_device_root_bus(const PCIDevice *d); const char *pci_root_bus_path(PCIDevice *dev); +bool pci_bus_bypass_iommu(PCIBus *bus); PCIDevice *pci_find_device(PCIBus *bus, int bus_num, uint8_t devfn); int pci_qdev_find_device(const char *id, PCIDevice **pdev); void pci_bus_get_w64_range(PCIBus *bus, Range *range); diff --git a/include/hw/pci/pci_host.h b/include/hw/pci/pci_host.h index 52e038c019..c6f4eb4585 100644 --- a/include/hw/pci/pci_host.h +++ b/include/hw/pci/pci_host.h @@ -43,6 +43,7 @@ struct PCIHostState { uint32_t config_reg; bool mig_enabled; PCIBus *bus; + bool bypass_iommu; QLIST_ENTRY(PCIHostState) next; };